char: adsprpc: fix global-out-of-bounds error

The array fastrpc_rpmsg_match is not ended with {}, out-of-bounds access
might occur when enumerating the ids listed in fastrpc_rpmsg_match.
Added {} to prevent out-of-bounds access.

bug: 189164670
Change-Id: Ia18e70c7739fca242c70187083c8fc651f98e968
Signed-off-by: JJ Lee <leejj@google.com>