radio: iris: Fix the set station issue at boundary

Seek frequency at lower/upper limit is not working
if selected country is in Europe band with channel
 spacing 50Khz

Use the correct upper limit for Europe band

Change-Id: Icdcb116c24ae9840cc66b1dc2da5fa739a2f89c8
CRs-Fixed: 338137
Signed-off-by: Ayaz Ahmad <aahmad@codeaurora.org>