cmd/vet: fix mips64le arch name in asmdecl check

Updates #11041

Change-Id: Ic6df8ef25b7cf280db523950cd3640b060ad1a9b
Reviewed-on: https://go-review.googlesource.com/27157
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

src/cmd/vet/asmdecl.go

@@ -74,7 +74,7 @@ var (
 	asmArchAmd64    = asmArch{"amd64", size88, false, "SP", false}
 	asmArchAmd64p32 = asmArch{"amd64p32", size48, false, "SP", false}
 	asmArchMips64   = asmArch{"mips64", size88, true, "R29", true}
-	asmArchMips64LE = asmArch{"mips64", size88, false, "R29", true}
+	asmArchMips64LE = asmArch{"mips64le", size88, false, "R29", true}
 	asmArchPpc64    = asmArch{"ppc64", size88, true, "R1", true}
 	asmArchPpc64LE  = asmArch{"ppc64le", size88, false, "R1", true}