Blackfin: SMP: implement cpu_freq support

Re-use some of the existing cpu hotplugging code in the process.

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

arch/blackfin/include/asm/dpmc.h

@@ -125,6 +125,9 @@ void unset_dram_srfs(void);
 
 #define VRPAIR(vlev, freq) (((vlev) << 16) | ((freq) >> 16))
 
+#ifdef CONFIG_CPU_FREQ
+#define CPUFREQ_CPU 0
+#endif
 struct bfin_dpmc_platform_data {
 	const unsigned int *tuple_tab;
 	unsigned short tabsize;