85xx boards: Rename CONFIG_DDR_DLL to CONFIG_SYS_FSL_ERRATUM_DDR_MSYNC_IN

This config option is for an erratum workaround; rename it to be more
clear.  Also, drop it from config files don't need it and were
undefining it.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/doc/README.mpc85xxads b/doc/README.mpc85xxads
index 046f981..d059a97 100644
--- a/doc/README.mpc85xxads
+++ b/doc/README.mpc85xxads
@@ -144,8 +144,8 @@
 			    also manual config the DDR after undef this
 			    definition.
     CONFIG_DDR_ECC	    only for ECC DDR module
-    CONFIG_DDR_DLL	    DLL fix on some ADS boards needed for more
-			    stability.
+    CONFIG_SYS_FSL_ERRATUM_DDR_MSYNC_IN	    DLL fix on some ADS boards needed
+			    for more stability.
     CONFIG_HAS_FEC	    If an FEC is on chip, set to 1, else 0.
 
 Other than the above definitions, the rest in the config files are