rtl8187: fix wrong register initialization in 8187B

We were using wrong address for BRSR (Basic Rate Set Register) while
initializing its value, comparing with Realtek sources, for 8187B case.

Also, the same register is initialized in rtl8187b_reg_table, so remove
the duplicate initialization from the table.

Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>