[ARM] 5428/1: Module relocation update for R_ARM_V4BX

It would seem when building kernel modules with modern binutils
(required by modern GCC) for ARM v4T targets (specifically observed
with the Samsung 24xx SoC which is an 920T) R_ARM_V4BX relocations
are emitted for function epilogues.

This manifests at module load time with an "unknown relocation: 40"
error message.

The following patch adds the R_ARM_V4BX relocation to the ARM kernel
module loader. The relocation operation is taken from that within the
binutils bfd library.

Signed-off-by: Simtec Linux Team <linux@simtec.co.uk>
Signed-off-by: Vincent Sanders <vince@simtec.co.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>