powerpc: Drop CONFIG_SYS_ALLOC_DPRAM

This is not defined anywhere in U-Boot. Drop this dead code.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/powerpc/cpu/mpc8xx/fec.c b/arch/powerpc/cpu/mpc8xx/fec.c
index 0940906..b27310f 100644
--- a/arch/powerpc/cpu/mpc8xx/fec.c
+++ b/arch/powerpc/cpu/mpc8xx/fec.c
@@ -570,14 +570,8 @@
 	rxIdx = 0;
 	txIdx = 0;
 
-	if (!rtx) {
-#ifdef CONFIG_SYS_ALLOC_DPRAM
-		rtx = (RTXBD *) (immr->im_cpm.cp_dpmem +
-				 dpram_alloc_align (sizeof (RTXBD), 8));
-#else
-		rtx = (RTXBD *) (immr->im_cpm.cp_dpmem + CPM_FEC_BASE);
-#endif
-	}
+	if (!rtx)
+		rtx = (RTXBD *)(immr->im_cpm.cp_dpmem + CPM_FEC_BASE);
 	/*
 	 * Setup Receiver Buffer Descriptors (13.14.24.18)
 	 * Settings: