TIMPresSelection not available for some mcu's

[fpistm]

Thanks @danieleff to report this:

Actually does not compile on 407 disco, timer.c:466:22: error: 'RCC_PeriphCLKInitTypeDef {aka struct }' has no member named 'TIMPresSelection'

Some STM32F4 mcu's do not have this member: See: stm32f4xx_hal_rcc_ex.h
STM32F405xx || STM32F415xx || STM32F407xx || STM32F417xx