Fix the name of the GNUmakefile

GNU make actually looks for ‘GNUmakefile’, not ‘GNUMakefile’.

Consequently, GNU make would erroneously attempt to use the standard
makefile, instead of the GNU-specific one. This would cause an error
when attempting to import png.h, due to PNGFLAGS not being correctly
set.
This commit is contained in:
Ben10do
2017-01-23 23:46:44 +00:00
parent f8531ed410
commit e86a70d2cb