Do not try to remove directories when removing old links
When building Git with MSVC on Windows, directories named after the Git
alias are created for the output files, e.g. there is a
"git-merge-index" directory next to the "git-merge-index.exe" executable
in the build root. Previously, "make all" just checked if
"git-merge-index" and "git-merge-index.exe" are the same file, and if
not, tried to remove "git-merge-index". This fails in the case of
"git-merge-index" being a directory, which is why this is checked now.
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>