powerpc/52xx: fix build breakage for MPC5200 LPBFIFO module

The MPC5200 LPBFIFO driver requires the bestcomm module to be
enabled, otherwise building will fail. Fix it.

Cc: <stable@vger.kernel.org> # 3.10+
Reported-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>

arch/powerpc/platforms/52xx/Kconfig

@@ -57,5 +57,5 @@ config PPC_MPC5200_BUGFIX
 
 config PPC_MPC5200_LPBFIFO
 	tristate "MPC5200 LocalPlus bus FIFO driver"
-	depends on PPC_MPC52xx
+	depends on PPC_MPC52xx && PPC_BESTCOMM
 	select PPC_BESTCOMM_GEN_BD