Compile git with OPENSSL_SHA1 and OPENSSL_SHA256 in FIPS mode
To be FIPS-compliant, we need to use a FIPS-validated OpenSSL for all cryptographic routines. As mentioned in https://github.com/git/git/blob/95acb13a550cbc07a5ef38ffceb5678fac61acff/Makefile#L176-L187, git-core has two environment variables we need to define when compiling git
in FIPS mode:
OPENSSL_SHA1
OPENSSL_SHA256
/cc: @pks-t