ppc: Check for compilers that don't support relocation

Certain ppc compilers are known not to generate the .fixup section
properly.  The .fixup section is necessary to create a relocatable
U-Boot image.  A basic check for the existence of the .fixup section
should hopefully catch the majority of broken compilers which don't
support relocation.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>

lib_ppc/Makefile

@@ -42,6 +42,12 @@ SRCS	:= $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
 OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
 
 $(LIB):	$(obj).depend $(OBJS)
+	@if ! $(CROSS_COMPILE)readelf -S $(OBJS) | grep -q '\.fixup.*PROGBITS';\
+	then \
+		echo "ERROR: Your compiler doesn't generate .fixup sections!";\
+		echo "       Upgrade to a recent toolchain."; \
+		exit 1; \
+	fi;
 	$(AR) $(ARFLAGS) $@ $(OBJS)
 
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