Add Gigabyte M61P-S3 SPI flash support to board_enable.c

Corresponding to flashrom svn r148 and coreboot v2 svn r2864.

Signed-off-by: Michael van der Kolff <mvanderkolff@gmail.com>
Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
diff --git a/README b/README
index 7e44d28..59a4299 100644
--- a/README
+++ b/README
@@ -55,7 +55,8 @@
 * ASUS P5A: use -m asus:p5a
 * IBM x3455: use -m ibm:x3455
 * EPoX EP-BX3: use -m epox:ep-bx3
-
+* GIGABYTE GA-M57SLI v2.0: use -m gigabyte:m57sli
+* GIGABYTE GA-M61P-S3: use -m gigabyte:m61ps3
 
 ROM Layout Support
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