TBR: devtools/madb: fix crash when setting a nickname for the first time.
TBR: devtools/madb: fix crash when setting a nickname for the first time.

Change-Id: I105b7742f8dafacbbafed2db8e6297f44c01c2b3

vanadium/go.devtools,vanadium/go.devtools,vanadium/go.devtools