x86/intel config: Fix the APB_TIMER selection

x86/intel config: Fix the APB_TIMER selection

Seems Kconfig SELECT isn't selecting things hierarchically when
selected.

config APB_TIMER
       def_bool y if X86_INTEL_MID
       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
       select DW_APB_TIMER
       depends on X86_INTEL_MID && SFI

when we select APB_TIMER doesn't select DW_APB_TIMER so do it by
hand.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-kpnaimplltk6d1lolusqj3ae@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>