package/nginx: remove rtsig module support

rtsig module uses the deprecated sysctl syscall, which is not
implemented on some recent architecture (such as arc).

Also, rtsig module is almost considered as deprecated by some nginx
developers [1].

So, just remove this option.

Fixes:
  http://autobuild.buildroot.org/results/730/730105fc0a89b381b3b29192d07f28ef1f13cbb3/

[1] http://mailman.nginx.org/pipermail/nginx-devel/2014-November/006295.html

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/nginx/Config.in

@@ -309,11 +309,6 @@ endif #BR2_PACKAGE_NGINX_MAIL
 
 comment "misc. modules"
 
-config BR2_PACKAGE_NGINX_RTSIG_MODULE
-	bool "ngx_rtsig_module"
-	help
-	  Enable ngx_rtsig_module
-
 config BR2_PACKAGE_NGINX_SELECT_MODULE
 	bool "ngx_select_module"
 	help

package/nginx/nginx.mk

@@ -88,7 +88,6 @@ endif
 
 # misc. modules
 NGINX_CONF_OPTS += \
-	$(if $(BR2_PACKAGE_NGINX_RTSIG_MODULE),--with-rtsig_module) \
 	$(if $(BR2_PACKAGE_NGINX_SELECT_MODULE),--with-select_module,--without-select_module) \
 	$(if $(BR2_PACKAGE_NGINX_POLL_MODULE),--with-poll_module,--without-poll_module)