Solaris m4/configure uses incorrect lib directory search paths for OpenSSL 3.0

Steps to reproduce:

1. use Solaris 10/11 with sparc or x86_64
2. compile static OpenSSL 3.0.3 and install in custom prefix
3. use --with-openssl=<some/path> pointing to the correct path of OpenSSL

Result:
"lib/64" directory not found

Expected:
https://www.openssl.org/news/changelog.html

On build targets where the multilib postfix is set in the build configuration the libdir directory was changing based on whether the lib directory with the multilib postfix exists on the system or not. This unpredictable behavior was removed and eventual multilib postfix is now always added to the default libdir.