gitclone: check for invalid patch filename

where the asterisk is used, it can sometimes
literally try to patch with a file named "*",
which of course does not exist

this change fixes an lbmk error when running:

./download seabios

this was caused recently, because all patches
were seabios were removed (lbmk currently uses
stock seabios, without patching it)

0 files changed, 0 insertions, 0 deletions