freescale: ls1043aqds: drop ifdef CONFIG_SYS_I2C

- Drop ifdef CONFIG_SYS_I2C to initialize
  baudrate of i2c

- Drop warning of i2c_early_init_f as follows,
  warning: implicit declaration of function 'i2c_early_init_f'; did you
  mean 'arch_early_init_r'? [-Wimplicit-function-declaration]

Signed-off-by: Biwen Li <biwen.li@nxp.com>
Reviewed-by: Priyanka Jain <priyanka.jain@nxp.com>