i2c: pxa: fix call balance of i2c->clk handling routines

If the clock i2c->clk was not enabled in i2c_pxa_probe(), it should not be
disabled in any path.

Found by Linux Verification Center (linuxtesting.org) with Klever.

Signed-off-by: Vitalii Mordan <mordan@ispras.ru>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250212172803.1422136-1-mordan@ispras.ru