uio: uio_fsl_elbc_gpcm: Add NULL check in uio_fsl_elbc_gpcm_probe devm_kasprintf() can return a NULL pointer on failure,but this info->mem[0].name returned value in uio_fsl_elbc_gpcm_probe is not checked. Add NULL check in uio_fsl_elbc_gpcm_probe, to handle kernel NULL pointer dereference error.