fix symbol 'util_cpu_caps' can not be used when making a shared object

Extern global variable 'util_cpu_caps' to multiple C source files is not a good habit, it caused linking failure when making a shard object in some cross compiling circumstance

Covert global variable to static and assign it only in one C source file, provide get function for other C source files

Signed-off-by: Hongxu Jia hongxu.jia@windriver.com