sparc32: Trivial removal of sun4c references in comments.

I left some around, like the ones in the openprom headers, since
we need to think about which pieces of those datastructures and
code we can completely toss now.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/include/asm/dma.h b/arch/sparc/include/asm/dma.h
index b554927..67e017f 100644
--- a/arch/sparc/include/asm/dma.h
+++ b/arch/sparc/include/asm/dma.h
@@ -123,8 +123,7 @@
  * Second mapping is for device visible address, or "bus" address.
  * The bus address is returned at '*pba'.
  *
- * These functions seem distinct, but are hard to split. On sun4c,
- * at least for now, 'a' is equal to bus address, and retured in *pba.
+ * These functions seem distinct, but are hard to split.
  * On sun4m, page attributes depend on the CPU type, so we have to
  * know if we are mapping RAM or I/O, so it has to be an additional argument
  * to a separate mapping function for CPU visible mappings.