Remove -march=native from build flags.

--- a/higan/GNUmakefile
+++ b/higan/GNUmakefile
@@ -26,7 +26,6 @@
   flags += -fopenmp
   link += -fopenmp
   ifeq ($(binary),application)
-    flags += -march=native
     link += -Wl,-export-dynamic
     link += -lX11 -lXext
   else ifeq ($(binary),library)
