ppc4xx: Big cleanup of PPC4xx defines

This patch cleans up multiple issues of the 4xx register (mostly
DCR, SDR, CPR, etc) definitions:

- Change lower case defines to upper case (plb4_acr -> PLB4_ACR)
- Change the defines to better match the names from the
  user's manuals (e.g. cprpllc -> CPR0_PLLC)
- Removal of some unused defines

Please test this patch intensive on your PPC4xx platform. Even though
I tried not to break anything and tested successfully on multiple
4xx AMCC platforms, testing on custom platforms is recommended.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/board/esd/pmc405de/pmc405de.c b/board/esd/pmc405de/pmc405de.c
index f68e1b5..419311a 100644
--- a/board/esd/pmc405de/pmc405de.c
+++ b/board/esd/pmc405de/pmc405de.c
@@ -127,7 +127,7 @@
 	 * - set ready timeout to 512 ebc-clks -> ca. 15 us
 	 * - EBC lines are always driven
 	 */
-	mtebc(epcr, 0xa8400000);
+	mtebc(EBC0_CFG, 0xa8400000);
 
 	return 0;
 }