toolchain/gcc: fix objective C suppor

We've had objective C support in the tree for many years, but somehow
the BR2_GCC_CROSS_OBJC option (similar to the other BR2_GCC_CROSS_*
options) has disappeared.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

toolchain/gcc/Config.in

@@ -56,6 +56,12 @@ config BR2_EXTRA_GCC_CONFIG_OPTIONS
 	help
 	  Any additional gcc configure options you may want to include....
 
+config BR2_GCC_CROSS_OBJC
+	bool "Objective-C cross-compiler support"
+	depends on !BR2_avr32
+	help
+	  Build an Objective-C cross-compiler
+
 config BR2_GCC_CROSS_FORTRAN
 	bool "Fortran cross-compiler support"
 	depends on !BR2_avr32