examples/embedding: Fix example so it compiles again.

There were a few changes that had broken this example, specifically
2cdf1d25 removed file.c from ports/unix.
And (at least for MacOS) mp_state_ctx must be placed in the BSS with
-fno-common so it is visible to the linker.
Signed-off-by: Santeri Paavolainen <santtu@iki.fi>

examples/embedding/Makefile.upylib

@@ -21,6 +21,9 @@ CWARN = -Wall -Werror
 CWARN += -Wpointer-arith -Wuninitialized
 CFLAGS = $(INC) $(CWARN) -std=gnu99 -DUNIX $(CFLAGS_MOD) $(COPT) $(CFLAGS_EXTRA)
 
+# Some systems (eg MacOS) need -fno-common so that mp_state_ctx is placed in the BSS.
+CFLAGS += -fno-common
+
 # Debugging/Optimization
 ifdef DEBUG
 CFLAGS += -g
@@ -133,7 +136,6 @@ SRC_C = $(addprefix ports/unix/,\
 	gccollect.c \
 	unix_mphal.c \
 	input.c \
-	file.c \
 	modmachine.c \
 	modos.c \
 	moduselect.c \
@@ -146,6 +148,7 @@ SRC_C = $(addprefix ports/unix/,\
 LIB_SRC_C = $(addprefix lib/,\
 	$(LIB_SRC_C_EXTRA) \
 	utils/printf.c \
+	utils/gchelper_generic.c \
 	timeutils/timeutils.c \
 	)