i2c: Update references to individual i2c commands

The individual i2c commands imd, imm, inm, imw, icrc32, iprobe, iloop,
and isdram are no longer available so all references to them have been
updated to the new form of "i2c <cmd>".

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
diff --git a/doc/README.ppc440 b/doc/README.ppc440
index 0a5f99f..1b96458 100644
--- a/doc/README.ppc440
+++ b/doc/README.ppc440
@@ -88,7 +88,7 @@
 =================
 
 The i2c utilities have been tested on both Rev B. and Rev C. and
-look good. The iprobe command implementation has been updated to
+look good. The 'i2c probe' command implementation has been updated to
 allow for 'skipped' addresses. Some i2c slaves are write only and
 cause problems when a probe (read) is performed (for example the
 CDCV850 clock controller at address 0x69 on the ebony board).
@@ -97,7 +97,7 @@
 CONFIG_SYS_I2C_NOPROBES macro in your board-specific header file. When
 defined, all specified addresses are skipped during a probe.
 The addresses that are skipped will be displayed in the output
-of the iprobe command.
+of the 'i2c probe' command.
 
 For example, to prevent probing address 0x69, define the macro as
 follows: