freetype: Delete a patch that is no longer used

Delete a patch that is no longer used

/meta-agl/meta-agl-core-test/recipes-test/freetype/files/0001-ft2demos-Makefile-Do-not-hardcode-libtool-path.patch
is already deleted from the file freetype_2.%.bbappend by https://git.automotivelinux.org/AGL/meta-agl/commit/meta-agl-core-test/recipes-test/freetype/freetype_2.%25.bbappend?id=f8e4906de8e21b9affb9f901527d587eb31b68ff and it was no longer used