powerpc/64: Have MPROFILE_KERNEL depend on FUNCTION_TRACER

Currently, it is possible to have CONFIG_FUNCTION_TRACER disabled, but
CONFIG_MPROFILE_KERNEL enabled. Though all existing users of
MPROFILE_KERNEL are doing the right thing, it is weird to have
MPROFILE_KERNEL enabled when the function tracer isn't. Fix this by
making MPROFILE_KERNEL depend on FUNCTION_TRACER.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200422092612.514301-1-naveen.n.rao@linux.vnet.ibm.com

arch/powerpc/Kconfig

@@ -476,7 +476,7 @@ config LD_HEAD_STUB_CATCH
 	  If unsure, say "N".
 
 config MPROFILE_KERNEL
-	depends on PPC64 && CPU_LITTLE_ENDIAN
+	depends on PPC64 && CPU_LITTLE_ENDIAN && FUNCTION_TRACER
 	def_bool $(success,$(srctree)/arch/powerpc/tools/gcc-check-mprofile-kernel.sh $(CC) -I$(srctree)/include -D__KERNEL__)
 
 config HOTPLUG_CPU