Fix gofmt problems and add gofmt to preupload checks

Test: gofmt -d .
Test: <bad change>, repo upload
Change-Id: I5ca0676461616f166a842d307c600dc50a50ec48

PREUPLOAD.cfg

@@ -0,0 +1,2 @@
+[Builtin Hooks]
+gofmt = true

cc/sanitize.go

@@ -25,9 +25,9 @@ import (
 )
 
 const (
-	asanCflags = "-fno-omit-frame-pointer"
+	asanCflags  = "-fno-omit-frame-pointer"
 	asanLdflags = "-Wl,-u,__asan_preinit"
-	asanLibs = "libasan"
+	asanLibs    = "libasan"
 )
 
 type sanitizerType int