clk: nxp: Remove unused variable

clk: nxp: Remove unused variable

GCC warns:

> ../drivers/clk/nxp/clk-lpc18xx-cgu.c: In function ‘lpc18xx_pll1_recalc_rate’:
> ../drivers/clk/nxp/clk-lpc18xx-cgu.c:460:13: warning: variable ‘stat’ set but not used [-Wunused-but-set-variable]
>   460 |         u32 stat, ctrl;
>       |             ^~~~

Get rid of the (apparently) useless read from the PLL1_STAT register and
the declaration of stat.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: b04e0b8fd5443 ("clk: add lpc18xx cgu clk driver")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/r/20220205103613.1216218-2-j.neuschaefer@gmx.net
Signed-off-by: Stephen Boyd <sboyd@kernel.org>