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/netstal/hcu4/hcu4.c b/board/netstal/hcu4/hcu4.c
index aa8a097..40bec8e 100644
--- a/board/netstal/hcu4/hcu4.c
+++ b/board/netstal/hcu4/hcu4.c
@@ -92,7 +92,7 @@
 	u16 index      = boardVersReg & 0x0f;
 
 	/* Cannot be done in board_early_init */
-	mtdcr(cntrl0,  CPC0_CR0_VALUE);
+	mtdcr(CPC0_CR0,  CPC0_CR0_VALUE);
 
 	/* Force /RTS to active. The board it not wired quite
 	 *  correctly to use cts/rtc flow control, so just force the