sparc: Sanitize cpu feature detection and reporting.

Instead of evaluating the cpu features for ELF_HWCAP every exec,
calculate it once at boot time.

Add AV_SPARC_* capability flag bits, compatible with what Solaris
reports to applications.

Report these capabilities once in the kernel log, and also via
/proc/cpuinfo in a new "cpucaps" entry.

If available, fetch the cpu features from the machine description
'hwcap-list' property of the 'cpu' node.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/cpu.c

@@ -396,6 +396,7 @@ static int show_cpuinfo(struct seq_file *m, void *__unused)
 		   , cpu_data(0).clock_tick
 #endif
 		);
+	cpucap_info(m);
 #ifdef CONFIG_SMP
 	smp_bogo(m);
 #endif