mingw-w64-git: use /proc/cygdrive prefix in bin path when installing …

…redirectors

If cygdrive is mounted to something other than `/` (e.g. `/mnt/`),
upgrading `mingw-w64-git` using pacman will result in redirectors (e.g.
`/bin/git.exe`) being installed to an incorrect path. (e.g. `C:/Program
Files/Git/bin` to `C:/Program Files/Git/C/Program Files/Git/bin`).

Signed-off-by: A2uria <[email protected]>
Signed-off-by: Johannes Schindelin <[email protected]>

mingw-w64-git/git.install

@@ -4,7 +4,7 @@ mingw_prefix_path () {
 }
 
 bin_path () {
-	echo "$(cygpath -am / | sed 's/^\([A-Z]\):/\/\1/')/bin"
+	echo "$(cygpath -am / | sed 's/^\([A-Z]\):/\/proc\/cygdrive\/\1/')/bin"
 }
 
 copy_files () {