sparc32: fix build failure for arch_jump_label_transform

In arch/sparc/Kernel/Makefile, we see:

   obj-$(CONFIG_SPARC64)   += jump_label.o

However, the Kconfig selects HAVE_ARCH_JUMP_LABEL unconditionally
for all SPARC.  This in turn leads to the following failure when
doing allmodconfig coverage builds:

kernel/built-in.o: In function `__jump_label_update':
jump_label.c:(.text+0x8560c): undefined reference to `arch_jump_label_transform'
kernel/built-in.o: In function `arch_jump_label_transform_static':
(.text+0x85cf4): undefined reference to `arch_jump_label_transform'
make: *** [vmlinux] Error 1

Change HAVE_ARCH_JUMP_LABEL to be conditional on SPARC64 so that it
matches the Makefile.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>