support few archs on Solaris for depot tools

depot_tools_solaris.diff

$ git show HEAD
commit e8480ae76179949c08c90b81fc3b16792b5f514c (HEAD -> solaris-os-supoort)
Author: Atiq Rahman <[email protected]>
Date:   Sun Jul 30 19:14:27 2017 -0700

    Support Solaris platform on a few arch

diff --git a/cipd b/cipd
index ef2e4ad5..f2884bff 100755
--- a/cipd
+++ b/cipd
@@ -22,14 +22,17 @@ case $UNAME in
   darwin)
     PLAT=mac
     ;;
-  *)
+  sunos)
+    PLAT=solaris
+    ;;
+ *)
     echo "UNKNOWN OS: $UNAME"
     exit 1
 esac

 UNAME=`uname -m | tr '[:upper:]' '[:lower:]'`
 case $UNAME in
-  x86_64|amd64)
+  x86_64|amd64|i86pc)
     ARCH=amd64
     ;;
   arm*)
@@ -38,6 +41,9 @@ case $UNAME in
   *86)
     ARCH=386
     ;;
+  sun4v)
+    ARCH=$UNAME
+    ;;
   *)
     echo "UNKNOWN Machine architecture: $UNAME"
     exit 1