build: fix build on cygwin
build: fix build on cygwin

On cygwin, <rpc/rpc.h> lives in a different directory than
/usr/include, so anything that uses it must modify CFLAGS.  This
previously tripped up just 'make check', but now that we build
all test programs unconditionally, it also trips up 'make'.

* tests/Makefile.am (virnetmessagetest_CFLAGS): Find rpc headers.

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