support nForce 430 southbridge-provided SATA drives.

Reference: /n/sources/patch/applied/nforce430-sb
Date: Sun Sep 17 20:22:13 CES 2006
Signed-off-by: quanstro@quanstro.net

--- /sys/src/9/pc/sdata.c	Sun Sep 17 20:21:32 2006
+++ /sys/src/9/pc/sdata.c	Sun Sep 17 20:21:09 2006
@@ -1968,6 +1968,8 @@
 		case (0x0053<<16)|0x10DE:	/* nVidia nForce4 */
 		case (0x0054<<16)|0x10DE:	/* nVidia nForce4 SATA */
 		case (0x0055<<16)|0x10DE:	/* nVidia nForce4 SATA */
+		case (0x0266<<16)|0x10DE:	// nVidia nForce4 430 southbridge
+		case (0x0267<<16)|0x10DE:	// nVidia nForce4 430 southbridge
 			/*
 			 * Ditto, although it may have a different base
 			 * address for the registers (0x50?).