ruby: Patch to enable building with clang

packages/ruby/configure.in.patch

@@ -0,0 +1,25 @@
+Fix issues when compiling with clang (where cpp is provided by gcc
+in the standalone toolchain).
+
+diff -u -r ../ruby-2.3.1/configure.in ./configure.in
+--- ../ruby-2.3.1/configure.in	2016-04-24 13:44:40.000000000 -0400
++++ ./configure.in	2016-05-18 01:10:09.523385169 -0400
+@@ -799,7 +799,7 @@
+ rb_cv_warnflags="$warnflags"
+ if test "$GCC:${warnflags+set}:no" = yes::no; then
+     if test $gcc_major -ge 4; then
+-	extra_warning=-Werror=extra-tokens
++	extra_warning=
+     else
+ 	extra_warning=
+     fi
+@@ -813,9 +813,7 @@
+ 		 -Werror=pointer-arith \
+ 		 -Werror=write-strings \
+ 		 -Werror=declaration-after-statement \
+-		 -Werror=shorten-64-to-32 \
+ 		 -Werror=implicit-function-declaration \
+-		 -Werror=division-by-zero \
+ 		 -Werror=deprecated-declarations \
+ 		 -Wno-packed-bitfield-compat \
+ 		 $extra_warning \