ASUS M5A88-V: Kconfig: Fix mainboard model name

Despite everywhere the model name M5A88-V is used, in Kconfig the
string M5A88PM-V is used. Searching for that model string on the
WWW does not return anything which is unrelated to coreboot, so
change that string to M5A88-V.

Change-Id: I25cf9d4a5fc3f9b9356e8616452066ebf873f44c
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-on: http://review.coreboot.org/2613
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martin.roth@se-eng.com>
Reviewed-by: QingPei Wang <wangqingpei@gmail.com>

src/mainboard/asus/m5a88-v/Kconfig

@@ -37,7 +37,7 @@ config APIC_ID_OFFSET
 
 config MAINBOARD_PART_NUMBER
 	string
-	default "M5A88PM-V"
+	default "M5A88-V"
 
 config HW_MEM_HOLE_SIZEK
 	hex