stm32g071 ADC drivers apply errata during sampling config

[FRASTM]

Describe the bug
When running the tests/drivers/dac/dac_loopback on the nucleo_g071rb, the dac loopback test case fails
The value read on the ADC channel 0 (pin PA0) is not correct.
The Sampling time is set at 1.5 cycle by the adc_stm32_setup_speed()

Please also mention any information which could help others to understand
the problem you're facing:

• What target platform are you using?
• What have you tried to diagnose or workaround this issue?
• ...

To Reproduce
Steps to reproduce the behavior:

1. west build -p auto -b nucleo_g071rb tests/drivers/dac/dac_loopback/
2. west flash
3. See error

Expected behavior
Test passed

Impact
Test coverage failure

Logs and console output

Running TESTSUITE dac_loopback_test                                             
===================================================================             
START - test_dac_loopback                                                       
                                                                                
    Assertion failed at WEST_TOPDIR/zephyr/tests/drivers/dac/dac_loopback/src/t)
Value 705 read from ADC does not match expected range.                          
 FAIL - test_dac_loopback in 0.31 seconds                                       
===================================================================             
TESTSUITE dac_loopback_test failed.                                             
===================================================================             
PROJECT EXECUTION FAILED     

Environment (please complete the following information):

• OS: Ubuntu
• Toolchain : zephyr 0.14.0
• Version used : 3.1.0-rc2

Additional context
Connect A0 to A2 pin (CN8) on the hw board to run the testcase