base: Fix get workload ea

This patch fixes a bug introduced by the
workload-num-blocks-reduce-code-size.patch that caused internal function
get_workload_ea() to return the wrong address.

Signed-off-by: Yuji Mano <yuji.mano@am.sony.com>
Acked-by: Kazunori Asayama <asayama@sm.sony.co.jp>