Revert "maintainers: fix Ruud's email"

The email for Ruud in the maintainers file actually matches his gerrit
ID.

This reverts commit 2a4e217.

Change-Id: I6739c9c383f485460d8ad72563c25e847ee04c57
Signed-off-by: Anas Nashif <anas.nashif@intel.com>

MAINTAINERS

@@ -60,7 +60,7 @@ Maintainers List (try to look for most precise areas first)
 		-----------------------------------
 
 ARC ARCHITECTURE
-M:	Ruud Derwig <rderwig@synopsys.com>
+M:	Ruud Derwig <Ruud.Derwig@synopsys.com>
 M:	Chuck Jordan <cjordan@synopsys.com>
 M:	Benjamin Walsh <benjamin.walsh@windriver.com>
 S:	Supported