Build block TWRP with RECOVERY_VARIANT

Enable TWRP to reside alongside other recoveries with the naming
convention: bootable/recovery(-flag). If TWRP resides at
bootable/recovery and a device does not specify RECOVERY_VARIANT, then
it will build like normal. If TWRP resides at bootable/recovery-twrp,
then its makefiles will only be parsed if a device specifies
'RECOVERY_VARIANT := twrp'. This prevents TWRP specific makefile
warnings/errors (notably, missing DEVICE_RESOLUTION) when another
recovery is being built.

Change-Id: I8f02fffcd79c309c7123b9428eedc69af02e126e
diff --git a/exfat/mkfs/Android.mk b/exfat/mkfs/Android.mk
index 8c48c77..fff04bd 100644
--- a/exfat/mkfs/Android.mk
+++ b/exfat/mkfs/Android.mk
@@ -8,8 +8,8 @@
 LOCAL_CFLAGS = -D_FILE_OFFSET_BITS=64
 LOCAL_SRC_FILES =  cbm.c fat.c main.c mkexfat.c rootdir.c uct.c uctc.c vbr.c
 LOCAL_C_INCLUDES += $(LOCAL_PATH) \
-					bootable/recovery/exfat/libexfat \
-					bootable/recovery/fuse/include
+					$(commands_recovery_local_path)/exfat/libexfat \
+					$(commands_recovery_local_path)/fuse/include
 LOCAL_SHARED_LIBRARIES += libz libc libexfat libdl 
 LOCAL_STATIC_LIBRARIES += libfusetwrp