uClibc: mark 0.9.31 as deprecated

0.9.31 is old and doesn't actually build with modern kernel headers,
so mark it as deprecated.

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

toolchain/uClibc/Config.in

@@ -11,6 +11,7 @@ choice
 
 	config BR2_UCLIBC_VERSION_0_9_31
 		bool "uClibc 0.9.31.x"
+		depends on BR2_DEPRECATED
 		depends on !BR2_xtensa
 
 	config BR2_UCLIBC_VERSION_0_9_32