Fix mmma uses like "mmma ./external/apache-harmony"

Fix mmma uses like "mmma ./external/apache-harmony" by removing the
leading ./ in entries in BUILD_MODULES_IN_PATHS.

Change-Id: I414e734c8a29434fc89ddb2b745613c33709c5e3
diff --git a/core/main.mk b/core/main.mk
index ffff1f7..d85bade 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -881,7 +881,8 @@
 all_modules: $(ALL_MODULES)
 else
 # BUILD_MODULES_IN_PATHS is a list of paths relative to the top of the tree
-module_path_patterns := $(foreach p, $(BUILD_MODULES_IN_PATHS),\
+build_modules_in_paths := $(patsubst ./%,%,$(BUILD_MODULES_IN_PATHS))
+module_path_patterns := $(foreach p, $(build_modules_in_paths),\
     $(if $(filter %/,$(p)),$(p)%,$(p)/%))
 my_all_modules := $(sort $(foreach m, $(ALL_MODULES),$(if $(filter\
     $(module_path_patterns), $(addsuffix /,$(ALL_MODULES.$(m).PATH))),$(m))))