rpm: added MODSRC_PREFIX to reduce diffs for pluggable modules.

rpm/SPECS/Makefile

diff --git a/rpm/SPECS/Makefile b/rpm/SPECS/Makefile
index a0feab8..56f3a50 100644
--- a/rpm/SPECS/Makefile
+++ b/rpm/SPECS/Makefile
@@ -5,7 +5,8 @@
 BASE_SRC=	nginx-$(BASE_VERSION).tar.gz
 SRCPATH?=	../SOURCES
 BUILD_ENV_PATH=	${HOME}/rpmbuild
-MODULE_TARGET?=	oss                                                     
+MODULE_TARGET?=	oss
+MODSRC_PREFIX=
 
 ifeq ($(MODULE_TARGET), plus)
 MODULE_SPEC_TEMPLATE=	nginx-plus-module.spec.in