s390/idle: Remove psw_idle() prototype

psw_idle() does not exist anymore. Remove its prototype.

Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

Author: hcahca

arch/s390/include/asm/idle.h

@@ -24,6 +24,4 @@ DECLARE_PER_CPU(struct s390_idle_data, s390_idle);
 extern struct device_attribute dev_attr_idle_count;
 extern struct device_attribute dev_attr_idle_time_us;
 
-void psw_idle(struct s390_idle_data *data, unsigned long psw_mask);
-
 #endif /* _S390_IDLE_H */