dcc_v2: Remove duplicate function

Remove duplicate is_dcc_enabled function introduced by
commit 2bc8103c ("dcc_v2: Don't set the default
value to sram when dcc is enabled").

Change-Id: I05f50b8b89b7433b889367cc080904d698b48f2f
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>