drivers/net/npe: descend only when CONFIG_IXP4XX_NPE=y

CONFIG_IXP4XX_NPE is defined only for CPU ixp.
It is not necessary to filter by CPU ixp.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

Makefile

@@ -242,9 +242,7 @@ LIBS-y += $(CPUDIR)/lib$(CPU).o
 ifdef SOC
 LIBS-y += $(CPUDIR)/$(SOC)/lib$(SOC).o
 endif
-ifeq ($(CPU),ixp)
-LIBS-y += drivers/net/npe/libnpe.o
-endif
+LIBS-$(CONFIG_IXP4XX_NPE) += drivers/net/npe/libnpe.o
 LIBS-$(CONFIG_OF_EMBED) += dts/libdts.o
 LIBS-y += arch/$(ARCH)/lib/lib$(ARCH).o
 LIBS-y += fs/libfs.o \

drivers/net/npe/Makefile

@@ -10,7 +10,7 @@ CFLAGS  += $(LOCAL_CFLAGS)
 CPPFLAGS  += $(LOCAL_CFLAGS) # needed for depend
 HOSTCFLAGS  += $(LOCAL_CFLAGS)
 
-obj-$(CONFIG_IXP4XX_NPE) := npe.o \
+obj-y := npe.o \
 	miiphy.o \
 	IxOsalBufferMgt.o \
 	IxOsalIoMem.o \