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/eric/eric.c b/board/eric/eric.c
index 600b9d7..bc2a907 100644
--- a/board/eric/eric.c
+++ b/board/eric/eric.c
@@ -70,7 +70,7 @@
 	mtdcr (uicvcr, 0x00000001);	/* set vect base=0,INT0 highest priority */
 	mtdcr (uicsr, 0xFFFFFFFF);	/* clear all ints */
 
-	mtdcr (cntrl0, 0x00002000);	/* set IRQ6 as GPIO23 to generate an interrupt request to the PCP2PCI bridge */
+	mtdcr (CPC0_CR0, 0x00002000);	/* set IRQ6 as GPIO23 to generate an interrupt request to the PCP2PCI bridge */
 
 	out32 (PPC405GP_GPIO0_OR, 0x60000000);	/*fixme is SMB_INT high or low active??; IRQ6 is GPIO23 output */
 	out32 (PPC405GP_GPIO0_TCR, 0x7E400000);