binutils: default to 2.21 on mips(el)

uClibc currently doesn't build on mips(el) with 2.21.1.

For details, see:

http://lists.uclibc.org/pipermail/uclibc/2011-March/045026.html

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

package/binutils/Config.in.host

@@ -2,6 +2,7 @@ comment "Binutils Options"
 
 choice
 	prompt "Binutils Version"
+	default BR2_BINUTILS_VERSION_2_21 if (BR2_mips || BR2_mipsel)
 	default BR2_BINUTILS_VERSION_2_21_1
 	help
 	  Select the version of binutils you wish to use.