www/firefox: unbreak build with devel/llvm13 (lacks patch-D77776)

Restore patch-bug1628567 to unbreak glslopt crate build due to cc crate
passing Rust target "x86_64-unknown-freebsd" without OS version to clang++:

[glslopt 0.1.9] cargo:warning=/wrkdirs/usr/ports/www/firefox/work/.build/
ist/system_wrappers/new:3:15: fatal error: 'new' file not found
[glslopt 0.1.9] cargo:warning=#include_next <new>

PR: 258837