Don't overwrite the static panicstr buffer for secondary and further panics. Before revision 1.38, we used to just point panicstr at the format string if panicstr was NULL, but since we now use a static buffer for the formatted panic message, we have to be careful to only write to it during the first panic.
Don't overwrite the static panicstr buffer for secondary and further
panics. Before revision 1.38, we used to just point panicstr at the
format string if panicstr was NULL, but since we now use a static
buffer for the formatted panic message, we have to be careful to
only write to it during the first panic.

Pointed out by:	bde

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase