pack-objects: hash basename and direname a bit differently.
pack-objects: hash basename and direname a bit differently.

...so that "Makefile"s from different revs are sorted together,
separate from "t/Makefile"s, but close enough.

Signed-off-by: Junio C Hamano <dc50d1021234060e53ec42a77d526afa2fe07479@cox.net>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git