Reworked pad timing with LA

[JonathanDotCel]

• Re-timed the pad timings to within a microsec or two
• removed the FIFO clear loop
• will read correct number of bytes (or max buffer size, whichever is smaller) for pads, mice, guns, etc.
• fixed timing for off spec SCPH 1080 (PS1 digital)
• fixed SCPH 10010 (A) timing (PS2 Dualshock, Alps)
• fixed timing with SCPH 1180 (PS1 dual analogue)
• fixed an issue with the Brook wireless adapter

[JonathanDotCel]

I'll tidy up the mismatched tabs/spaces comment indentation in a bit.