[SYCL][CodeOwners] Update CodeOwners file to reflect CFE changes (#1834)

In an attempt to better cross train the CFE team on reviews, we're
rotating our code reviewers.  Elizabeth/Prem are going to replace Erich,
with Mariya taking over as the expert.

Author: Erich Keane

.github/CODEOWNERS

@@ -1,6 +1,6 @@
 * @bader
 
-clang/ @erichkeane @Fznamznon
+clang/ @Fznamznon @premanandrao @elizabethandrews
 
 clang/**/Driver @mdtoguchi @AGindinson