enable gdbserver for cris, checked basic usage on foxboard

package/gdbserver/Makefile

@@ -9,8 +9,6 @@ PKG_SECTION:=		debug
 PKG_DEPENDS:=		libthread-db
 PKG_SUBPKGS:=		GDBSERVER
 
-PKG_ARCH_DEPENDS:=	!cris
-
 WRKSRC=                 ${WRKDIST}/gdb/gdbserver
 
 include ${TOPDIR}/mk/package.mk

package/gdbserver/patches/patch-gdb_gdbserver_linux-cris-low_c

@@ -0,0 +1,11 @@
+--- gdb-7.1.orig/gdb/gdbserver/linux-cris-low.c
++++ gdb-7.1/gdb/gdbserver/linux-cris-low.c
+@@ -62,7 +62,7 @@
+ extern int debug_threads;
+ 
+ static CORE_ADDR
+-cris_get_pc (struct regcache *regcache, void)
++cris_get_pc (struct regcache *regcache)
+ {
+   unsigned long pc;
+   collect_register_by_name (regcache, "pc", &pc);