drivers/firmware/dmi_scan.c: make dmi_name_in_vendors more focused

The current implementation of dmi_name_in_vendors() is an invitation to
lazy coding and false positives [1].  Searching for a string in 8 know
what you're looking for, so you should know where to look.  strstr isn't
fast, especially when it fails, so we should avoid calling it when it
just can't succeed.

Looking at the current users of the function, it seems clear to me that
they are looking for a system or board vendor name, so let's limit
dmi_name_in_vendors to these two DMI fields.  This much better matches
the function name, BTW.

[1] We currently have code looking for short names in DMI data, such as
"IBM", "ASUS" or "Acer".  I let you guess what will happen the day other
vendors ship products named, for example, "SCHREIBMEISTER", "PEGASUS" or
"Acerola".
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/firmware/dmi_scan.c

@@ -585,14 +585,12 @@ int dmi_name_in_serial(const char *str)
 }
 
 /**
- *	dmi_name_in_vendors - Check if string is anywhere in the DMI vendor information.
+ *	dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
  *	@str: 	Case sensitive Name
  */
 int dmi_name_in_vendors(const char *str)
 {
-	static int fields[] = { DMI_BIOS_VENDOR, DMI_BIOS_VERSION, DMI_SYS_VENDOR,
-				DMI_PRODUCT_NAME, DMI_PRODUCT_VERSION, DMI_BOARD_VENDOR,
-				DMI_BOARD_NAME, DMI_BOARD_VERSION, DMI_NONE };
+	static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
 	int i;
 	for (i = 0; fields[i] != DMI_NONE; i++) {
 		int f = fields[i];