Revert "lib: build list_sort() only if needed"

This reverts commit a069c266ae5fdfbf5b4aecf2c672413aa33b2504.

It turns ou that not only was it missing a case (XFS) that needed it,
but perhaps more importantly, people sometimes want to enable new
modules that they hadn't had enabled before, and if such a module uses
list_sort(), it can't easily be inserted any more.

So rather than add a "select LIST_SORT" to the XFS case, just leave it
compiled in. It's not all _that_ big, after all, and the inconvenience
isn't worth it.

Requested-by: Alexey Dobriyan <[e-mail]>
Cc: Christoph Hellwig <[e-mail]>
Cc: Don Mullis <[e-mail]>
Cc: Andrew Morton <[e-mail]>
Cc: Dave Chinner <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/gpu/drm/Kconfig

···
 	depends on (AGP || AGP=n) && PCI && !EMULATED_CMPXCHG && MMU
 	select I2C
 	select I2C_ALGOBIT
-	select LIST_SORT
 	help
 	  Kernel-level support for the Direct Rendering Infrastructure (DRI)
 	  introduced in XFree86 4.0. If you say Y here, you need to select

fs/ubifs/Kconfig

···
 	select CRYPTO if UBIFS_FS_ZLIB
 	select CRYPTO_LZO if UBIFS_FS_LZO
 	select CRYPTO_DEFLATE if UBIFS_FS_ZLIB
-	select LIST_SORT
 	depends on MTD_UBI
 	help
 	  UBIFS is a file system for flash devices which works on top of UBI.

lib/Kconfig

···
 config TEXTSEARCH_FSM
 	tristate
 
-config LIST_SORT
-	boolean
-
 config BTREE
 	boolean
 

lib/Makefile

···
 
 obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
 	 bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
-	 string_helpers.o gcd.o
+	 string_helpers.o gcd.o list_sort.o
 
 ifeq ($(CONFIG_DEBUG_KOBJECT),y)
 CFLAGS_kobject.o += -DDEBUG
···
 lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
 obj-$(CONFIG_GENERIC_FIND_LAST_BIT) += find_last_bit.o
 obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o
-obj-$(CONFIG_LIST_SORT) += list_sort.o
 obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
 obj-$(CONFIG_BTREE) += btree.o
 obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o