ARM: 5872/1: ARM: include needed linux/cpu.h in asm/cpu.h

The file arch/arm/include/asm/cpu.h needs to include 'linux/cpu.h' to
meet its dependency. Otherwise when using "struct cpuinfo_arm" and
including just 'asm/cpu.h' throws below error -
	arch/arm/include/asm/cpu.h:16: error: field 'cpu' has incomplete type

To fix this  otherway, one can also include both linux/cpu.h and
asm/cpu.h but it shoudn't be that way.  So this patch fixes this by
including the linux/cpu.h in asm/cpu.h, so that including alone
asm/cpu.h is enough.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>