mwifiex: support custom world regulatory domain

country 00 (world regulatory domain) doesn't define channels
52 - 64 and 100 - 140. Add these channels to our custom world
regulatory domain.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>