ARM: module: ignore unwind for sections not marked SHF_ALLOC

If a section is not marked with SHF_ALLOC, it will be discarded
by the module code.  Therefore, it is not correct to register
the unwind tables.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index f9937c4..0c1bb68 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -290,6 +290,9 @@
 	for (s = sechdrs; s < sechdrs_end; s++) {
 		const char *secname = secstrs + s->sh_name;
 
+		if (!(s->sh_flags & SHF_ALLOC))
+			continue;
+
 		if (strcmp(".ARM.exidx.init.text", secname) == 0)
 			maps[ARM_SEC_INIT].unw_sec = s;
 		else if (strcmp(".ARM.exidx.devinit.text", secname) == 0)