Add AL value to debugger interrupt breakpoints. Useful for breaking on specific sub-functions, and for function numbers in AX such as the mouse driver INT 33h. Faster breakpoint checking with some redundant conditions removed.

git-svn-id: http://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3849 ed541006-0bf7-43e9-8c4d-6fc63c346d47
The SB DMA callback ignores previously selected, but not currently selected, DMA channels. Fixes Visual Player 2 with SB16.

Bits 0 and 4 of the SBPro mixer volume registers are always set. Fixes SBPro detection in Wolfenstein 3D, Alone in the Dark (European versions), Visual Player 2, and possibly others.

git-svn-id: http://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@3850 ed541006-0bf7-43e9-8c4d-6fc63c346d47