libc/eglibc: enable rpc in eglibc-2.16+

While eglibc-2.16 recommends to use TI-RPC instead of the old sunrpc, the
old one can be included using a configure option. Since the user can still
use TI-RPC to override the libc implementation, we enable rpc unconditionally.

Signed-off-by: Johannes Stezenbach <js@sig21.net>
Message-Id: <20121102140404.GA7707@sig21.net>
Patchwork-Id: 196564

 # Blackfin specific configuration file

 ## select ARCH_SUPPORTS_32

 ## select ARCH_DEFAULT_32

 ## select ARCH_DEFAULT_LE

 ## select ARCH_SUPPORTS_WITH_ARCH

 ## select ARCH_SUPPORTS_WITH_CPU

 ## select ARCH_SUPPORTS_WITH_TUNE

 ## select ARCH_SUPPORTS_WITH_FPU

 ##

 ## help The Blackfin architecture