[STM32F4] Clock and interrupt fixes#1735

Merged

0xc0170 merged 2 commits intoARMmbed:masterfrom

BartSX:stm32f4_can

May 16, 2016

Commits on May 12, 2016

[STM32F4] Get PCLK1 clock and set initial CAN frequency
BartSX
committed

Commits on May 13, 2016

[STM32F4] Fix for CAN2 interrupt index
BartSX
committed