m68k: atari - Rename "mfp" to "st_mfp"

http://kisskb.ellerman.id.au/kisskb/buildresult/72115/:
| net/mac80211/ieee80211_i.h:327: error: syntax error before 'volatile'
| net/mac80211/ieee80211_i.h:350: error: syntax error before '}' token
| net/mac80211/ieee80211_i.h:455: error: field 'sta' has incomplete type
| distcc[19430] ERROR: compile net/mac80211/main.c on sprygo/32 failed

This is caused by

| # define mfp ((*(volatile struct MFP*)MFP_BAS))

in arch/m68k/include/asm/atarihw.h, which conflicts with the new "mfp" enum in
net/mac80211/ieee80211_i.h.

Rename "mfp" to "st_mfp", as it's a way too generic name for a global #define.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index 69e1df7..4234c11 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -1730,7 +1730,7 @@
 
 	timeout = jiffies + 2*HZ+HZ/2;
 	while (time_before(jiffies, timeout))
-		if (!(mfp.par_dt_reg & 0x20))
+		if (!(st_mfp.par_dt_reg & 0x20))
 			break;
 
 	status = FDC_READ( FDCREG_STATUS );
@@ -1747,7 +1747,7 @@
 		/* dummy seek command to make WP bit accessible */
 		FDC_WRITE( FDCREG_DATA, 0 );
 		FDC_WRITE( FDCREG_CMD, FDCCMD_SEEK );
-		while( mfp.par_dt_reg & 0x20 )
+		while( st_mfp.par_dt_reg & 0x20 )
 			;
 		status = FDC_READ( FDCREG_STATUS );
 	}