clk: bcm2835: Remove unused variable

clk: bcm2835: Remove unused variable

Since commit 8ca011ef4af4 ("clk: bcm-2835: Remove rounding up the
dividers"), the rem variable is still set but no longer used. Remove it.

Fixes: 8ca011ef4af4 ("clk: bcm-2835: Remove rounding up the dividers")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220222140732.253819-1-maxime@cerno.tech
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>