Make NESEMU1 demo more reliable

This program was originally ported to Cosmopolitan before we had threads
so it was designed to use a single thread. That caused issues for people
with slower computers, like an Intel Core i5, where Gyarados would go so
slow that the audio would skip. I would also get audio skipping when the
terminal was put in full screen mode. Now we use two threads and smarter
timing, so NESEMU1 should go reliably fast on everyone's computer today.

examples/BUILD.mk

@@ -150,6 +150,10 @@ o/$(MODE)/examples/picol.o: private				\
 		CPPFLAGS +=					\
 			-DSTACK_FRAME_UNLIMITED
 
+o/$(MODE)/examples/nesemu1.o: private				\
+		CPPFLAGS +=					\
+			-O3
+
 o/$(MODE)/examples/picol.dbg:					\
 		$(EXAMPLES_DEPS)				\
 		o/$(MODE)/examples/picol.o			\