ARM: 8958/1: rename missed uaccess .fixup section

When the uaccess .fixup section was renamed to .text.fixup, one case was
missed. Under ld.bfd, the orphaned section was moved close to .text
(since they share the "ax" bits), so things would work normally on
uaccess faults. Under ld.lld, the orphaned section was placed outside
the .text section, making it unreachable.

Link: https://github.com/ClangBuiltLinux/linux/issues/282
Link: https://bugs.chromium.org/p/chromium/issues/detail?id=1020633#c44
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.1912032147340.17114@knanqh.ubzr
Link: https://lore.kernel.org/lkml/202002071754.F5F073F1D@keescook/

Fixes: c4a84ae3 ("ARM: 8322/1: keep .text and .fixup regions closer together")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

arch/arm/lib/copy_from_user.S

@@ -118,7 +118,7 @@ ENTRY(arm_copy_from_user)
 
 ENDPROC(arm_copy_from_user)
 
-	.pushsection .fixup,"ax"
+	.pushsection .text.fixup,"ax"
 	.align 0
 	copy_abort_preamble
 	ldmfd	sp!, {r1, r2, r3}