Use the individual library versions in LibreSSL pc files

Previously, they were all using the portable package version, rather
than the individual library versions. openssl(1)'s pc file represents
the LibreSSL-portable release however.

$ pkg-config --modversion libtls
1:0:0
$ pkg-config --modversion openssl
2.1.2
$ pkg-config --modversion libssl
30:0:0
$ pkg-config --modversion libcrypto
30:3:0

ok beck@ deraadt@
add LIBADD library dependencies to libssl/libtls

From Jan Engelhardt
allow Windows DLLs to be built

based on a patch from Jan Engelhardt
bump version

append portable version number to the version string