STM32F7 Bootloader unable to jump to application
You should adjust your linker scripts to reflect the fact that the programs are to be loaded to separate flash areas. So, for the bootloader you need

FLASH (rx)      : ORIGIN = 0x08000000, LENGTH = 32K


and for the application:

FLASH (rx)      : ORIGIN = 0x08008000, LENGTH = 992K /* (992 = 1024 - 32 */