Add INTLLIBS back into librazor_la_LIBADD and also into razor.pc

Add INTLLIBS back into librazor_la_LIBADD and also into razor.pc

INTLLIBS was originally added into librazor_la_LIBADD (but not razor.pc)
in 611c84a3f4b4538a65d186050608c17adbf17770 and then removed in
236cfc8ecc5c66288e41bf9b72051a3b18326e1c over concerns that it meant
that building static applications (eg., in plover) required a static
version of libintl. Since then, however, the inclusion of gnulib's
getopt has caused the build to fail without INTLLIBS in librazor_la_LIBADD
with messages of the form:

../gl/.libs/libgnu.a(getopt.o): In function `_getopt_internal_r':
/home/ali/wk/razor/vpath/gl/../../working/gl/getopt.c:808: undefined reference to `libintl_gettext'

while building librazor.dll.a

Thus it appears that INTLLIBS really is needed and should go back into
librazor_la_LIBADD (which fixes the build) and should also be in Libs.private
in razor.pc for static builds. This means that a static version of libintl
will be required (eg., as part of mingw64-gettext-static).

Along the way, razor.pc has also been fixed to avoid overlinking
(https://wiki.openmandriva.org/en/Overlinking_issues_in_packaging)
and a missing include directory that caused the razor executable to
fail to build was added.