msrtool: add support for cs5536 LPC_SERIRQ (0x5140004e)

This register is helpful for porting new mainboards based on
cs5536 southbridge.

Change-Id: Iff3adc2c2fbc672c8541096756f95b3322f6ab19
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-on: http://review.coreboot.org/1211
Reviewed-by: Anton Kochkov <anton.kochkov@gmail.com>
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
1 file changed