MM_FillMem doesn't call MM_SegmentBreak like read from or write to file

[skliper]

Checklist (Please check before submitting)

• I reviewed the Contributing Guide.
• I reviewed the README file to see if the feature is in the major future work.
• I performed a cursory search to see if the feature request is relevant, not redundant, nor in conflict with other tickets.

Is your feature request related to a problem? Please describe.
MM_FillMem writes memory in a tight loop here with no MM_SegmentBreak:

MM/fsw/src/mm_load.c

Lines 825 to 839 in 90cbd8d

	/* Fill memory one segment at a time */
	while (BytesRemaining != 0)
	{
	/* Last fill segment may be partial size */
	if (BytesRemaining < MM_MAX_FILL_DATA_SEG)
	{
	SegmentSize = BytesRemaining;
	}
	memcpy(TargetPointer, FillBuffer, SegmentSize);
	TargetPointer += SegmentSize;
	BytesProcessed += SegmentSize;
	BytesRemaining -= SegmentSize;
	}

Both MM_LoadMemFromFile and MM_DumpMemToFile do have a MM_SegmentBreak (example):

MM/fsw/src/mm_load.c

Lines 576 to 604 in 90cbd8d

	while (BytesRemaining != 0)
	{
	if (BytesRemaining < MM_MAX_LOAD_DATA_SEG)
	{
	SegmentSize = BytesRemaining;
	}
	if ((ReadLength = OS_read(FileHandle, ioBuffer, SegmentSize)) == SegmentSize)
	{
	memcpy(TargetPointer, ioBuffer, SegmentSize);
	BytesRemaining -= SegmentSize;
	BytesProcessed += SegmentSize;
	TargetPointer += SegmentSize;
	/* Prevent CPU hogging between load segments */
	if (BytesRemaining != 0)
	{
	MM_SegmentBreak();
	}
	}
	else
	{
	CFE_EVS_SendEvent(MM_OS_READ_ERR_EID, CFE_EVS_EventType_ERROR,
	"OS_read error received: RC = 0x%08X Expected = %d File = '%s'", (unsigned int)ReadLength,
	(int)SegmentSize, FileName);
	BytesRemaining = 0;
	}
	}

MM_FillMem is likely quicker, but should still support a break

Describe the solution you'd like
Add MM_SegmentBreak

Describe alternatives you've considered
Could leave as is, but large fill command processing could hog the CPU

Additional context
None

Requester Info
Jacob Hageman - NASA/GSFC