config: some refactoring.

Author: agentzh

config

@@ -1,5 +1,21 @@
 ngx_addon_name=ngx_http_headers_more_filter_module
-HTTP_AUX_FILTER_MODULES="$HTTP_AUX_FILTER_MODULES ngx_http_headers_more_filter_module"
-NGX_ADDON_SRCS="$NGX_ADDON_SRCS $ngx_addon_dir/src/ngx_http_headers_more_filter_module.c $ngx_addon_dir/src/ngx_http_headers_more_headers_out.c $ngx_addon_dir/src/ngx_http_headers_more_headers_in.c $ngx_addon_dir/src/ngx_http_headers_more_util.c"
-NGX_ADDON_DEPS="$NGX_ADDON_DEPS $ngx_addon_dir/src/ddebug.h $ngx_addon_dir/src/ngx_http_headers_more_filter_module.h $ngx_addon_dir/src/ngx_http_headers_more_headers_in.h $ngx_addon_dir/src/ngx_http_headers_more_headers_out.h $ngx_addon_dir/src/ngx_http_headers_more_headers_in.h $ngx_addon_dir/src/ngx_http_headers_more_util.h"
 
+HEADERS_MORE_SRCS="                                                         \
+                $ngx_addon_dir/src/ngx_http_headers_more_filter_module.c    \
+                $ngx_addon_dir/src/ngx_http_headers_more_headers_out.c      \
+                $ngx_addon_dir/src/ngx_http_headers_more_headers_in.c       \
+                $ngx_addon_dir/src/ngx_http_headers_more_util.c             \
+                "
+
+HEADERS_MORE_DEPS="                                                         \
+                $ngx_addon_dir/src/ddebug.h                                 \
+                $ngx_addon_dir/src/ngx_http_headers_more_filter_module.h    \
+                $ngx_addon_dir/src/ngx_http_headers_more_headers_in.h       \
+                $ngx_addon_dir/src/ngx_http_headers_more_headers_out.h      \
+                $ngx_addon_dir/src/ngx_http_headers_more_headers_in.h       \
+                $ngx_addon_dir/src/ngx_http_headers_more_util.h             \
+                "
+
+HTTP_AUX_FILTER_MODULES="$HTTP_AUX_FILTER_MODULES $ngx_addon_name"
+NGX_ADDON_SRCS="$NGX_ADDON_SRCS $HEADERS_MORE_SRCS"
+NGX_ADDON_DEPS="$NGX_ADDON_DEPS $HEADERS_MORE_DEPS"