kbuild,gcov: simplify kernel/gcov/Makefile

Kbuild descends into kernel/gcov/ directory only when
CONFIG_GCOV_KERNEL is enabled. (See kernel/Makefile)

CONFIG_GCOV_KERNEL check can be omitted in kernel/gcov/Makefile.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

kernel/gcov/Makefile

@@ -13,10 +13,10 @@ else
   cc-ver := $(cc-version)
 endif
 
-obj-$(CONFIG_GCOV_KERNEL) := base.o fs.o
+obj-y := base.o fs.o
 
 ifeq ($(call if-lt, $(cc-ver), 0407),1)
-  obj-$(CONFIG_GCOV_KERNEL) += gcc_3_4.o
+  obj-y += gcc_3_4.o
 else
-  obj-$(CONFIG_GCOV_KERNEL) += gcc_4_7.o
+  obj-y += gcc_4_7.o
 endif