config: Set some default TWRP flags

When WITH_TWRP=true is set:
* Set recovery variant to TWRP, it should be synced
  under bootable/recovery-twrp in Lineage
* Exclude SuperSU, we have our own su solution

Change-Id: I5e5e6f2b42282c4666cdc013405a1488a9c6341d

config/common.mk

@@ -92,6 +92,11 @@ ifneq ($(TARGET_DISABLE_CMSDK), true)
 include vendor/cm/config/cmsdk_common.mk
 endif
 
+# TWRP
+ifeq ($(WITH_TWRP),true)
+include vendor/cm/config/twrp.mk
+endif
+
 # Bootanimation
 PRODUCT_PACKAGES += \
     bootanimation.zip

config/twrp.mk

@@ -0,0 +1,2 @@
+RECOVERY_VARIANT := twrp
+TW_EXCLUDE_SUPERSU := true