proc/gdbserial: use --unmask-signal debugserver option (#2255)
proc/gdbserial: use --unmask-signal debugserver option (#2255)

Fixes #852

Co-authored-by: a <86f7e437faa5a7fce15d1ddcb9eaeaea377667b8@kra>
aarzilli/delve,go-delve/delve,go-delve/delve,aarzilli/delve,aarzilli/delve,go-delve/delve,go-delve/delve,aarzilli/delve,go-delve/delve