radio: initialize spacing to default value.

Initialize spacing to default value 0 to avoid undefined behaviour in some
code branches.

Change-Id: I072e507b005236a4d08fa192135b37e32780d59c
CRs-fixed: 1070487
Signed-off-by: Smriti Gupta <smritig@codeaurora.org>
Signed-off-by: Rupesh Tatiya <rtatiya@codeaurora.org>