Fix conv FSM freeze

[hngenc]

Made these changes to fix conv FSM:

• Fix a_stride updates in ROB
• Make the ROB's block_mvin raw checks less cautious
• Stop GARBAGE_ADDRs from being considered as hazards in ROB
• Fix a typo in LoopConv/LdInput

Made these changes to improve performance:

• Replaced downsampling layers with a series of strided matmuls
• Improved conv tiling factor selection
• Added block-mvout for resadds
• Add config options for the ExecuteController to only read data from the spad, and only write data to the accumulator. This eliminates RAW-hazard checking delays in the ExecuteController.

Performance:

• ResNet50: 153709356 cycles (40% utilization)