MIPS: Remove code protected by CONFIG_SYS_HAS_CPU_RM9000.

RM9000 support was removed a while ago but this bit crept back in through
commit 69f24d17 [MIPS: Optimize current_cpu_type() for better code.] which
had been developed before but merged after RM9000 support was removed.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Reported-by: NPaul Bolle <pebolle@tiscali.nl>

arch/mips/include/asm/cpu-type.h

@@ -155,9 +155,6 @@ static inline int __pure __get_cpu_type(const int cpu_type)
 	case CPU_RM7000:
 	case CPU_SR71000:
 #endif
-#ifdef CONFIG_SYS_HAS_CPU_RM9000
-	case CPU_RM9000:
-#endif
 #ifdef CONFIG_SYS_HAS_CPU_SB1
 	case CPU_SB1:
 	case CPU_SB1A: