BMIPS: Enable prerequisites for CPUfreq in MIPS Kconfig.

Turn on CPU_SUPPORTS_CPUFREQ and MIPS_EXTERNAL_TIMER for BMIPS.
Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

arch/mips/Kconfig

@@ -1703,6 +1703,8 @@ config CPU_BMIPS
 	select WEAK_ORDERING
 	select CPU_SUPPORTS_HIGHMEM
 	select CPU_HAS_PREFETCH
+	select CPU_SUPPORTS_CPUFREQ
+	select MIPS_EXTERNAL_TIMER
 	help
 	  Support for BMIPS32/3300/4350/4380 and BMIPS5000 processors.