build: fix 'make distcheck' with pdwtags installed
build: fix 'make distcheck' with pdwtags installed

I am getting this failure with 'make distcheck':

  GEN    ../../src/remote_protocol-structs
/bin/sh: ../../src/remote_protocol-structs-t: Permission denied
make[4]: *** [../../src/remote_protocol-structs] Error 1

since it attempts a sub-run of a VPATH 'make check' where $(srcdir)
is intentionally read-only.  I'm not sure which commit introduced
the problem, although I suspect it was around 62dee6f when I
refactored protocol struct checking to be more powerful.

$(@F) is required by POSIX, and although it is not yet portable
to all make implementations, we already require GNU make.

* src/Makefile.am (PDWTAGS): Generate temp file into current
directory, since $(srcdir) is read-only during distcheck.

soulxu/libvirt-xuhj,wiedi/libvirt,agx/libvirt,rmarwaha/libvirt,wiedi/libvirt,rmarwaha/libvirt,novel/fbsd-libvirt,shugaoye/libvirt,taget/libvirt,eskultety/libvirt,foomango/libvirt,elmarco/libvirt,agx/libvirt,shugaoye/libvirt,taget/libvirt,VenkatDatta/libvirt,elmarco/libvirt,jeckersb/libvirt,rlaager/libvirt,usc-isi/libvirt,elmarco/libvirt,novel/fbsd-libvirt,rmarwaha/libvirt1,datto/libvirt,jardasgit/libvirt,emaste/libvirt,novel/fbsd-libvirt,datto/libvirt,crobinso/libvirt,andreabolognani/libvirt,cbosdo/libvirt,shugaoye/libvirt,datto/libvirt,andreabolognani/libvirt,datto/libvirt,shugaoye/libvirt,zippy2/libvirt,fabianfreyer/libvirt,VenkatDatta/libvirt,jeckersb/libvirt,rlaager/libvirt,leilihh/libvirt,fabianfreyer/libvirt,crobinso/libvirt,nertpinx/libvirt,emaste/libvirt,zhlcindy/libvirt-1.1.4-maintain,bjzhang/libvirt,wiedi/libvirt,bjzhang/libvirt,andreabolognani/libvirt,rlaager/libvirt,danwent/libvirt-ovs,elmarco/libvirt,danwent/libvirt-ovs,fabianfreyer/libvirt,emaste/libvirt,warewolf/libvirt,warewolf/libvirt,eskultety/libvirt,dumbbell/libvirt,jfehlig/libvirt,danwent/libvirt-ovs,agx/libvirt,nertpinx/libvirt,datto/libvirt,libvirt/libvirt,rmarwaha/libvirt1,dumbbell/libvirt,rmarwaha/libvirt1,emaste/libvirt,leilihh/libvirt,trainstack/libvirt,eskultety/libvirt,trainstack/libvirt,warewolf/libvirt,trainstack/libvirt,rmarwaha/libvirt,siboulet/libvirt-openvz,foomango/libvirt,warewolf/libvirt,wiedi/libvirt,leilihh/libvirt,jfehlig/libvirt,nertpinx/libvirt,emaste/libvirt,jeckersb/libvirt,novel/fbsd-libvirt,danwent/libvirt-ovs,trainstack/libvirt,rmarwaha/libvirt1,bjzhang/libvirt,zhlcindy/libvirt-1.1.4-maintain,leilihh/libvirt,rlaager/libvirt,trainstack/libvirt,trainstack/libvirt,iam-TJ/libvirt,jeckersb/libvirt,agx/libvirt,crobinso/libvirt,olafhering/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,usc-isi/libvirt,VenkatDatta/libvirt,cbosdo/libvirt,soulxu/libvirt-xuhj,siboulet/libvirt-openvz,dumbbell/libvirt,zippy2/libvirt,olafhering/libvirt,warewolf/libvirt,rmarwaha/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,usc-isi/libvirt,iam-TJ/libvirt,libvirt/libvirt,jeckersb/libvirt,danwent/libvirt-ovs,soulxu/libvirt-xuhj,zhlcindy/libvirt-1.1.4-maintain,nertpinx/libvirt,crobinso/libvirt,wiedi/libvirt,novel/fbsd-libvirt,olafhering/libvirt,bjzhang/libvirt,emaste/libvirt,novel/fbsd-libvirt,novel/fbsd-libvirt,zhlcindy/libvirt-1.1.4-maintain,eskultety/libvirt,wiedi/libvirt,rlaager/libvirt,libvirt/libvirt,olafhering/libvirt,wiedi/libvirt,bjzhang/libvirt,jfehlig/libvirt,emaste/libvirt,eskultety/libvirt,novel/fbsd-libvirt,dumbbell/libvirt,foomango/libvirt,trainstack/libvirt,iam-TJ/libvirt,iam-TJ/libvirt,siboulet/libvirt-openvz,rmarwaha/libvirt,jardasgit/libvirt,iam-TJ/libvirt,jardasgit/libvirt,cbosdo/libvirt,iam-TJ/libvirt,shugaoye/libvirt,andreabolognani/libvirt,warewolf/libvirt,cbosdo/libvirt,foomango/libvirt,elmarco/libvirt,taget/libvirt,taget/libvirt,usc-isi/libvirt,leilihh/libvirt,soulxu/libvirt-xuhj,jeckersb/libvirt,novel/fbsd-libvirt,dumbbell/libvirt,usc-isi/libvirt,agx/libvirt,jfehlig/libvirt,soulxu/libvirt-xuhj,rmarwaha/libvirt1,jardasgit/libvirt,siboulet/libvirt-openvz,foomango/libvirt,VenkatDatta/libvirt,leilihh/libvirt,warewolf/libvirt,dumbbell/libvirt,libvirt/libvirt,rmarwaha/libvirt,cbosdo/libvirt,andreabolognani/libvirt,iam-TJ/libvirt,zippy2/libvirt,rmarwaha/libvirt1,taget/libvirt,jeckersb/libvirt,zhlcindy/libvirt-1.1.4-maintain,siboulet/libvirt-openvz,fabianfreyer/libvirt,zippy2/libvirt