powerpc: Drop -fno-dwarf2-cfi-asm

The original commit/discussion adding -fno-dwarf2-cfi-asm refers to
R_PPC64_REL32 relocations not being handled by our module loader:
http://lkml.kernel.org/r/20090224065112.GA6690@bombadil.infradead.org

However, that is now handled thanks to commit 9f751b82
("powerpc/module: Add support for R_PPC64_REL32 relocations").

So, drop this flag from our Makefile.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9b22a064de6eb1301d92177eb3a38559df7005d3.1583415544.git.naveen.n.rao@linux.vnet.ibm.com

arch/powerpc/Makefile

@@ -239,11 +239,6 @@ KBUILD_CFLAGS += $(call cc-option,-mno-vsx)
 KBUILD_CFLAGS += $(call cc-option,-mno-spe)
 KBUILD_CFLAGS += $(call cc-option,-mspe=no)
 
-# FIXME: the module load should be taught about the additional relocs
-# generated by this.
-# revert to pre-gcc-4.4 behaviour of .eh_frame
-KBUILD_CFLAGS	+= $(call cc-option,-fno-dwarf2-cfi-asm)
-
 # Never use string load/store instructions as they are
 # often slow when they are implemented at all
 KBUILD_CFLAGS		+= $(call cc-option,-mno-string)