There is a chance 'cpu_has_fpu' would still be overridden when the
CONFIG_MIPS_FP_SUPPORT configuration option has been disabled. So
add a safety check for 'cpu_has_fpu'.
Suggested-by: NMaciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: NShida Zhang <zhangshida@kylinos.cn>
Signed-off-by: NThomas Bogendoerfer <tsbogend@alpha.franken.de>