stm32cube: update stm32f1xx cube version to V1.8.0

Update Cube version for STM32F1XX series
from version: V1.7.0
to version: V1.8.0

Includes following fixes:
    *Update LSI_VALUE to 40 KHz
     Impacted files:
      drivers/include/stm32f1xx_ll_rcc.h
     ST Bug tracker ID: 37419

    *Use of (__packed uint32_t *) produces warning
      Using GNU 8.2.0, (__packed uint32_t *) generates warning.
      Replace with CMSIS macros __UNALIGNED_UINT32_READ and
      __UNALIGNED_UINT32_WRITE.
     Impacted files:
      drivers/include/stm32f1xx_ll_usb.c
     ST Bug tracker ID: 61323

    *Fix warnings for extraneous parentheses
      Using clang 7.0.1, if ((htim->State == HAL_TIM_STATE_BUSY))
      generates warnings.  Remove the extra parentheses
     Impacted files:
      drivers/src/stm32f1xx_hal_tim.c
      drivers/src/stm32f1xx_hal_tim_ex.c
     ST Bug tracker ID: 63614


Signed-off-by: Erwan Gouriou <erwan.gouriou@linaro.org>