Cleanup: fix "MHz" spelling

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/drivers/net/natsemi.c b/drivers/net/natsemi.c
index ff8d2d7..ce12c3b 100644
--- a/drivers/net/natsemi.c
+++ b/drivers/net/natsemi.c
@@ -409,7 +409,7 @@
    The EEPROM code is for common 93c06/46 EEPROMs w/ 6bit addresses.  */
 
 /* Delay between EEPROM clock transitions.
-   No extra delay is needed with 33Mhz PCI, but future 66Mhz
+   No extra delay is needed with 33MHz PCI, but future 66MHz
    access may need a delay. */
 #define eeprom_delay(ee_addr)	INL(dev, ee_addr)
 
diff --git a/drivers/net/ns8382x.c b/drivers/net/ns8382x.c
index a2d61af..198f73d 100644
--- a/drivers/net/ns8382x.c
+++ b/drivers/net/ns8382x.c
@@ -445,7 +445,7 @@
 	Read and write MII registers using software-generated serial MDIO
 	protocol.  See the MII specifications or DP83840A data sheet for details.
 
-	The maximum data clock rate is 2.5 Mhz.  To meet minimum timing we
+	The maximum data clock rate is 2.5 MHz.  To meet minimum timing we
 	must flush writes to the PCI bus with a PCI read. */
 #define mdio_delay(mdio_addr) INL(dev, mdio_addr)
 
diff --git a/drivers/net/rtl8139.c b/drivers/net/rtl8139.c
index d378ce3..db8a727 100644
--- a/drivers/net/rtl8139.c
+++ b/drivers/net/rtl8139.c
@@ -287,7 +287,7 @@
 
 /*
 	Delay between EEPROM clock transitions.
-	No extra delay is needed with 33Mhz PCI, but 66Mhz may change this.
+	No extra delay is needed with 33MHz PCI, but 66MHz may change this.
 */
 
 #define eeprom_delay()	inl(ee_addr)
diff --git a/drivers/net/tigon3.c b/drivers/net/tigon3.c
index ab448b0..e4e004e 100644
--- a/drivers/net/tigon3.c
+++ b/drivers/net/tigon3.c
@@ -2247,7 +2247,7 @@
 	REG_WR (pDevice, Grc.Mode, Value32);
 
 	/* Setup the timer prescalar register. */
-	REG_WR (pDevice, Grc.MiscCfg, 65 << 1);	/* Clock is alwasy 66Mhz. */
+	REG_WR (pDevice, Grc.MiscCfg, 65 << 1);	/* Clock is alwasy 66MHz. */
 
 	/* Set up the MBUF pool base address and size. */
 	REG_WR (pDevice, BufMgr.MbufPoolAddr, pDevice->MbufBase);