Fix typo on STM32 i2c driver
Fix typo on STM32 i2c driver

	On STM32 discovery board build fails due to
	a typo on chip/stm32/i2c-stm32l.c in assignement

BUG=none

Change-Id: I8e01006f70165b797472eb367e70aebb8dcb9502
Signed-off-by: Mario Tesi <8b284eac44479183e0767bb69fe1165781bd25a2@st.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1720392
Reviewed-by: Daisuke Nojiri <fd5f93af191bf7e8f73ea71cc3c0f66b41b1dd49@chromium.org>
Reviewed-by: Denis Brockus <6b21e8190fb5e373363fb95271367073a16474ef@chromium.org>
Commit-Queue: Denis Brockus <6b21e8190fb5e373363fb95271367073a16474ef@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec