(MESS) a7800.c - Numerous Improvements/bugfixes
 * Proper calibration per Diagnostic cart [Mike Saarna]
 * PAL RIOT fixed. [Mike Saarna]
 * Corrected SYNC timing to match later GCC tech doc and measurements against real hw [Mike Saarna]
 * Fix to bug that causes skip to first DLL if its 1 scanline tall. [Mike Saarna]
 * Fixed total horiz pixels to better match hw testing results and tech docs.  Fixed rendering to ensure DMA stolen cycles. [Mike Saarna]
 * Fixes reading of controller port behavior when held high by RIOT chip [Mike Saarna]
 * Normalize horizontal frequency while maintaining same net cycles. [Robert Tuccitto]
 * Fixed a few remaining issues while keeping to documented tech specs and ranges. [Mike Saarna/Robert Tuccitto]
 * Correct fix to Maria cycles regarding DMA Shutdown short/other line shutdown. [Mike Saarna/Robert Tuccitto]