Remove the unnecessary indirection of TARGET_STRIP_COMMAND

Now all archs use the same strip command which can be put just in
transform-to-stripped.

Change-Id: Ief79697d47ea142fc9e63e63a7e2dace9e839165
diff --git a/core/definitions.mk b/core/definitions.mk
index d6cd9d1..a449f0e 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -1321,16 +1321,23 @@
 ## Commands for filtering a target executable or library
 ###########################################################
 
+ifneq ($(TARGET_BUILD_VARIANT),user)
+  TARGET_STRIP_EXTRA = && $(PRIVATE_OBJCOPY) --add-gnu-debuglink=$< $@
+  TARGET_STRIP_KEEP_SYMBOLS_EXTRA = --add-gnu-debuglink=$<
+endif
+
 define transform-to-stripped
 @mkdir -p $(dir $@)
 @echo "target Strip: $(PRIVATE_MODULE) ($@)"
-$(hide) $($(PRIVATE_2ND_ARCH_VAR_PREFIX)TARGET_STRIP_COMMAND)
+$(hide) $(PRIVATE_STRIP) --strip-all $< -o $@ $(TARGET_STRIP_EXTRA)
 endef
 
 define transform-to-stripped-keep-symbols
 @mkdir -p $(dir $@)
 @echo "target Strip (keep symbols): $(PRIVATE_MODULE) ($@)"
-$(hide) $($(PRIVATE_2ND_ARCH_VAR_PREFIX)TARGET_STRIP_KEEP_SYMBOLS_COMMAND)
+$(hide) $(PRIVATE_OBJCOPY) \
+    `$(PRIVATE_READELF) -S $< | awk '/.debug_/ {print "-R " $$2}' | xargs` \
+    $(TARGET_STRIP_KEEP_SYMBOLS_EXTRA) $< $@
 endef