multi-line ACLOCAL_AMFLAGS isn't supported by autoreconf.
It will cause configure error as follow.

   aclocal: error: non-option arguments are not accepted: '\'.

Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>

diff -Nurp libgxim-0.5.0.orig/Makefile.am libgxim-0.5.0/Makefile.am
--- libgxim-0.5.0.orig/Makefile.am	2012-12-13 15:48:09.000000000 +0800
+++ libgxim-0.5.0/Makefile.am	2014-12-19 11:05:50.727209821 +0800
@@ -2,9 +2,7 @@ NULL =
 AUTOMAKE_OPTIONS = dist-bzip2
 SUBDIRS = libgxim m4macros po tests docs
 
-ACLOCAL_AMFLAGS =			\
-	-I m4macros			\
-	$(NULL)
+ACLOCAL_AMFLAGS = -I m4macros $(NULL)
 
 CONFIGURE_DEPENDENCIES =		\
 	requires			\