fix two IDE warnings

I got the following warnings in 2.4.25-pre7:

<-- snip -->

...
gcc-2.95 -D__KERNEL__ -I/home/bunk/linux/kernel-2.4/linux-2.4.25-pre7-full/include -Wall -Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common -fomit-frame-pointer -pipe -mpreferred-stack-boundary=2 -march=k6 -I../ -nostdinc -iwithprefix include -DKBUILD_BASENAME=siimage -c -o siimage.o siimage.c
siimage.c: In function `pdev_is_sata':
siimage.c:65: warning: control reaches end of non-void function
...
gcc-2.95 -D__KERNEL__ -I/home/bunk/linux/kernel-2.4/linux-2.4.25-pre7-full/include -Wall -Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common -fomit-frame-pointer -pipe -mpreferred-stack-boundary=2 -march=k6 -I../ -nostdinc -iwithprefix include -DKBUILD_BASENAME=generic -c -o generic.o generic.c
generic.h:151: warning: `unknown_chipset' defined but not used
...

<-- snip -->

The patch below (completely stolen from 2.6) fixes these two warnings.

Please apply
Adrian

@@ -62,6 +62,7 @@
 			return 0;
 	}
 	BUG();
+	return 0;
 }
  
 /**

@@ -148,6 +148,7 @@
 	}
 };
 
+#if 0
 static ide_pci_device_t unknown_chipset[] __devinitdata = {
 	{	/* 0 */
 		.vendor		= 0,

@@ -170,5 +171,6 @@
 	}
 
 };
+#endif
 
 #endif /* IDE_GENERIC_H */