Remove "VECTRESET is not supported" on RP2350

[earlephilhower]

The "cortex_m reset_config sysresetreq" setting in the RP2350.tcl script doesn't seem to set the value for core1, leading to warning messages during successful runs:

Warn : [rp2350.dap.core1] VECTRESET is not supported on this Cortex-M core, using SYSRESETREQ instead.
Warn : [rp2350.dap.core1] Set 'cortex_m reset_config sysresetreq'.

Explicitly add the setting to the RP2350 config file to silence the warnings.

Fixes #120