Hello victorgomez,
First change the FS type of ur SD card from FAT32 to EXT4, it might be create problem.
Its something wrong here about mmcdev,
mmc1 is current device
do as below and revert back with result.
try to change the mmc1 to mmc0
so new one will become like this
setenv bootcmd_microsd 'mmc dev 1; fatload mmc 0:1 ${loadaddr} ifs-mx6q-sabrelite.raw; go ${loadaddr}'
and be sure that ur uImage is in partition 1 od SD card, bcoz u specify mmcpart = 1 in argument, so if it not in that partition then change the mmcpart argument accordingly to it.
setenv bootcmd_microsd 'mmc dev 1; fatload mmc 0:1 ${loadaddr} ifs-mx6q-sabrelite.raw; go ${loadaddr}'
u change the bold digit in above arguments.
and if possible then provide me complete boot argument of ut U-boot, it will give better idea.
Hope it will help u,
Regards
Jaymin D