build: cleanup using $<

No need to list the first prerequisite. No functional changes.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Makefile

@@ -1705,9 +1705,9 @@ version.sp version.s version.o: EXTRA_CPPFLAGS = \
 
 $(BUILT_INS): git$X
 	$(QUIET_BUILT_IN)$(RM) $@ && \
-	ln git$X $@ 2>/dev/null || \
-	ln -s git$X $@ 2>/dev/null || \
-	cp git$X $@
+	ln $< $@ 2>/dev/null || \
+	ln -s $< $@ 2>/dev/null || \
+	cp $< $@
 
 common-cmds.h: ./generate-cmdlist.sh command-list.txt
 
@@ -1772,7 +1772,7 @@ $(patsubst %.perl,%,$(SCRIPT_PERL)): % : %.perl GIT-VERSION-FILE
 	    -e '	x' \
 	    -e '}' \
 	    -e 's/@@GIT_VERSION@@/$(GIT_VERSION)/g' \
-	    $@.perl >$@+ && \
+	    $< >$@+ && \
 	chmod +x $@+ && \
 	mv $@+ $@
 
@@ -1805,7 +1805,7 @@ $(SCRIPT_PYTHON_GEN): % : %.py
 	sed -e '1s|#!.*python|#!$(PYTHON_PATH_SQ)|' \
 	    -e 's|\(os\.getenv("GITPYTHONLIB"\)[^)]*)|\1,"@@INSTLIBDIR@@")|' \
 	    -e 's|@@INSTLIBDIR@@|'"$$INSTLIBDIR"'|g' \
-	    $@.py >$@+ && \
+	    $< >$@+ && \
 	chmod +x $@+ && \
 	mv $@+ $@
 else # NO_PYTHON