scsi: aacraid: Fix I/O drop during reset

"FIB_CONTEXT_FLAG_TIMEDOUT" flag is set in aac_eh_abort to indicate
command timeout. Using the same flag in reset handler causes the command
to time out and the I/Os were dropped.

Define a new flag "FIB_CONTEXT_FLAG_EH_RESET" to make sure I/O is
properly handled in eh_reset handler.

[mkp: tweaked commit message]

Signed-off-by: Prasad B Munirathnam <prasad.munirathnam@microsemi.com>
Reviewed-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>