kernel: handle Cavium Octeon Kconfig rename

Upstream commit 9ddebc46 ("MIPS: OCTEON: Rename Kconfig
CAVIUM_OCTEON_REFERENCE_BOARD to CAVIUM_OCTEON_SOC") renamed a Kconfig
symbol, thus making all MIPS builds ask for this specific Kconfig
symbol, add it.

Signed-off-by: Florian Fainelli <[email protected]>

SVN-Revision: 38535

target/linux/generic/config-3.12

@@ -515,6 +515,7 @@ CONFIG_CARDBUS=y
 CONFIG_CAVIUM_OCTEON_HELPER=y
 # CONFIG_CAVIUM_OCTEON_REFERENCE_BOARD is not set
 # CONFIG_CAVIUM_OCTEON_SIMULATOR is not set
+# CONFIG_CAVIUM_OCTEON_SOC is not set
 # CONFIG_CB710_CORE is not set
 # CONFIG_CC_OPTIMIZE_FOR_SIZE is not set
 # CONFIG_CC_STACKPROTECTOR is not set