Clarify the help for PLL MUL value of STM32L0
Clarify the help for PLL MUL value of STM32L0

The phrase "product is in Range 1" doesn't make it clear that it is
about "voltage scale mode".
CezaryGapinski/distortos,CezaryGapinski/distortos,DISTORTEC/distortos,DISTORTEC/distortos,jasmin-j/distortos,jasmin-j/distortos,jasmin-j/distortos,DISTORTEC/distortos,CezaryGapinski/distortos,jasmin-j/distortos,DISTORTEC/distortos,CezaryGapinski/distortos,CezaryGapinski/distortos,jasmin-j/distortos