mongrel2: allow to build for sparc

With uClibc-ng 1.0.15 sparc support got context functions.
Tested with qemu-system-sparc.

Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/mongrel2/Config.in

@@ -5,7 +5,7 @@ config BR2_PACKAGE_MONGREL2_LIBC_SUPPORTS
 	bool
 	default y if BR2_TOOLCHAIN_USES_GLIBC
 	default y if BR2_TOOLCHAIN_USES_UCLIBC && \
-		(BR2_arm || BR2_armeb || BR2_i386 || BR2_mips || BR2_mipsel || BR2_mips64 || BR2_mips64el || BR2_x86_64)
+		(BR2_arm || BR2_armeb || BR2_i386 || BR2_mips || BR2_mipsel || BR2_mips64 || BR2_mips64el || BR2_sparc || BR2_x86_64)
 
 comment "mongrel2 needs a uClibc or glibc toolchain w/ C++, threads, wchar, dynamic library"
 	depends on !BR2_INSTALL_LIBSTDCPP || \