Meta: Add a LINK alias to the common makefile for running ld explicitly

Author: https://github.com/deoxxa
Commit: https://github.com/SerenityOS/serenity/commit/0706bf470fc
Pull-request: https://github.com/SerenityOS/serenity/pull/565
Reviewed-by: https://github.com/awesomekling

Makefile.common

@@ -33,6 +33,7 @@ CXXFLAGS = -MMD -MP $(WARNING_FLAGS) $(OPTIMIZATION_FLAGS) $(FLAVOR_FLAGS) $(ARC
 CXX = $(PRE_CXX) i686-pc-serenity-g++
 LD = i686-pc-serenity-g++
 AS = i686-pc-serenity-as
+LINK = i686-pc-serenity-ld
 
 DEFINES = -DSANITIZE_PTRS -DDEBUG