s390/decompressor: rename entry point to startup_decompressor

Rename the decompressor entry point to startup_decompressor to
avoid confusion, leaving startup_continue as the entry point of the
uncompressed image.

Also remove obsolete comment, as the decompressor code is
unconditionally called from boot/head.S now.
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/boot/compressed/head.S

@@ -15,7 +15,7 @@
 #include "sizes.h"
 
 __HEAD
-ENTRY(startup_continue)
+ENTRY(startup_decompressor)
 	basr	%r13,0			# get base
 .LPG1:
 	# setup stack

arch/s390/boot/head.S

@@ -310,10 +310,7 @@ ENTRY(startup_kdump)
 	l	%r15,.Lstack-.LPG0(%r13)
 	ahi	%r15,-STACK_FRAME_OVERHEAD
 	brasl	%r14,verify_facilities
-# For uncompressed images, continue in
-# arch/s390/kernel/head64.S. For compressed images, continue in
-# arch/s390/boot/compressed/head.S.
-	jg	startup_continue
+	jg	startup_decompressor
 
 .Lstack:
 	.long	0x8000 + (1<<(PAGE_SHIFT+THREAD_SIZE_ORDER))