Remove SUBSYS.o rule in common.mk, hasn't been used in a long time

Apparently I missed that this SUBSYS.o rule isn't needed anymore in
a4ebbd27527, likely because there still is a reference to it due to AIX - but
that's self contained in src/backend/Makefile

Discussion: https://postgr.es/m/20220820174213.d574qde4ptwdzoqz@awork3.anarazel.de

diff --git a/src/backend/common.mk b/src/backend/common.mk
index 663e9f886ced2a77a08be854201c596db34de503..fa96a82b1a0cc4a1b004877dc0e12d24e1c0fa87 100644 (file)
--- a/src/backend/common.mk
+++ b/src/backend/common.mk
@@ -17,9 +17,6 @@ ifneq ($(subdir), src/backend)
 all: $(subsysfilename)
 endif
 
-SUBSYS.o: $(SUBDIROBJS) $(OBJS)
-   $(LD) $(LDREL) $(LDOUT) $@ $^
-
 objfiles.txt: Makefile $(SUBDIROBJS) $(OBJS)
 # Don't rebuild the list if only the OBJS have changed.
    $(if $(filter-out $(OBJS),$?),( $(if $(SUBDIROBJS),cat $(SUBDIROBJS); )echo $(addprefix $(subdir)/,$(OBJS)) ) >$@,touch $@)