src/tests/Makefile.am: fix compilation with OpenSSL
src/tests/Makefile.am: fix compilation with OpenSSL

OpenSSL header files are used indirectly by the binaries.

Fix the compilation error:
  CC       base64.o
In file included from base64.c:6:
In file included from ../../src/libopensc/asn1.h:29:
In file included from ../../src/libopensc/pkcs15.h:29:
In file included from ../../src/libopensc/aux-data.h:31:
In file included from ../../src/libopensc/internal.h:44:
../../src/libopensc/sc-ossl-compat.h:30:10: fatal error: 'openssl/opensslv.h'
      file not found
         ^
1 error generated.

mtrojnar/OpenSC,AktivCo/OpenSC,Jakuje/OpenSC,mouse07410/OpenSC,jpki/OpenSC,Jakuje/OpenSC,hongquan/OpenSC-main,metsma/OpenSC,Jakuje/OpenSC,martinpaljak/OpenSC,frankmorgner/OpenSC,philipWendland/OpenSC,viktorTarasov/OpenSC-SM,OpenSC/OpenSC,nmav/OpenSC,philipWendland/OpenSC,AktivCo/OpenSC,hongquan/OpenSC-main,fabled/OpenSC,mouse07410/OpenSC,viktorTarasov/OpenSC-SM,LudovicRousseau/OpenSC,AktivCo/OpenSC,mouse07410/OpenSC,Jakuje/OpenSC,nmav/OpenSC,mtrojnar/OpenSC,LudovicRousseau/OpenSC,dengert/OpenSC,OpenSC/OpenSC,CardContact/OpenSC,martinpaljak/OpenSC,metsma/OpenSC,jpki/OpenSC,viktorTarasov/OpenSC-SM,rickyepoderi/OpenSC,fabled/OpenSC,martinpaljak/OpenSC,hhonkanen/OpenSC,fabled/OpenSC,frankmorgner/OpenSC,OpenSC/OpenSC,LudovicRousseau/OpenSC,mtrojnar/OpenSC,dengert/OpenSC,hongquan/OpenSC-main,CardContact/OpenSC,CardContact/OpenSC,frankmorgner/OpenSC,philipWendland/OpenSC,hhonkanen/OpenSC,rickyepoderi/OpenSC,metsma/OpenSC,frankmorgner/OpenSC,rickyepoderi/OpenSC,fabled/OpenSC,dengert/OpenSC,hhonkanen/OpenSC,jpki/OpenSC,nmav/OpenSC