[Bug 51877] New: improve POSIX compatibility for wine-staging's patches/gitapply.sh

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=51877

Bug ID: 51877
           Summary: improve POSIX compatibility for wine-staging's
                    patches/gitapply.sh
           Product: Wine-staging
           Version: 6.19
          Hardware: x86-64
                OS: other
            Status: NEW
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
                CC: [e-mail], [e-mail]

Created attachment 70802
  --> https://bugs.winehq.org/attachment.cgi?id=70802
Makes patches/gitapply.sh more POSIX compatible

wine-staging's patches/patchinstall.sh can apply patches using Git commands, or
CLI tools. It prefers Git commands, but when it detects that some parent
directory is a Git repository, it passes --nogit to patches/gitapply.sh, which
then starts using CLI tools which use various Linuxisms.

On FreeBSD, the Git commands work, but since the Ports tree can itself be a Git
repository, and Wine extracts under it (by default), they cannot always be
used, falling back to CLI tools with Linuxisms that break.

This patch makes patches/gitapply.sh more POSIX compatible, and gets it working
on FreeBSD.