devel/libspice-server: fix pc file generation
libspice-server uses autotools and utilizes PKG_CHECK_MODULES to get
openssl CFLAGS and LDFLAGS. However, as we support various openssl flavors,
including openssl from base that lacks pkg-config file, we explicitly pass
OPENSSL_LIBS and OPENSSL_CFLAGS via CONFIGURE_ENV, however, libspice-server
still adds 'openssl' package to Requires.private of its .pc file.
This causes a problem for software that requires libspice-server, because
e.g. when using openssl from base, detection will fail because .pc file
is listing non-existent 'openssl' package.
To fix that, update libspice-server's configure.ac to add 'openssl' to
Requires.private only if OPENSSL_LIBS and OPENSSL_CFLAGS wasn't explicitly
specified by user, otherwise omit 'openssl' and just add
the value of OPENSSL_LIBS to Libs.private.
While here, add 'amd64' to list of x86_64 cpus so it don't show a warning.
Also, drop RUN_DEPENDS on spice-protocol as this is basically a set of
headers and it's not required in runtime.
Reviewed by: maintainer
Differential Revision: https://reviews.freebsd.org/D13896