dashboard: update linux-mipsle-mengzhuo info

We don't need GOARCH and GOHOSTARCH for linux-mipsle-mengzhuo since
this box is mips64le dispite the name.

Change-Id: I81253de96141513d7ee54c8b8bd21fe2c482fc72
Reviewed-on: https://go-review.googlesource.com/c/build/+/346271
Reviewed-by: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Trust: Meng Zhuo <mzh@golangcn.org>
Run-TryBot: Meng Zhuo <mzh@golangcn.org>
TryBot-Result: Go Bot <gobot@golang.org>
diff --git a/dashboard/builders.go b/dashboard/builders.go
index a268ca8..7323c77 100644
--- a/dashboard/builders.go
+++ b/dashboard/builders.go
@@ -580,7 +580,7 @@
 		env:         []string{"GOROOT_BOOTSTRAP=/opt/golang/go-solaris-amd64-bootstrap"},
 	},
 	"host-linux-mipsle-mengzhuo": &HostConfig{
-		Notes:       "Loongson 3A Box hosted by Meng Zhuo; actually MIPS64 despite the name",
+		Notes:       "Loongson 3A Box hosted by Meng Zhuo; actually MIPS64le despite the name",
 		OwnerGithub: "mengzhuo",
 		IsReverse:   true,
 		ExpectNum:   1,
@@ -2364,10 +2364,6 @@
 		SkipSnapshot:   true,
 		distTestAdjust: mipsDistTestPolicy,
 		buildsRepo:     mipsBuildsRepoPolicy,
-		env: []string{
-			"GOARCH=mips64le",
-			"GOHOSTARCH=mips64le",
-		},
 	})
 	addBuilder(BuildConfig{
 		FlakyNet:       true,