needed for spice/common files used by the client, server & qxl driver.
in windows _inline works for both c/c++, while inline is c++ only.
compiling the client with mixed c/c++ code required this define.
spice_common.h provides an ASSERT macro, no need to duplicate it
in many places. For now client/debug.h keeps its own copy since
debug.h and spice_common.h have clashes on other macros which are
trickier to unify.
When using config.h, it must be the very first include in all source
files since it contains #define that may change the compilation process
(eg libc structure layout changes when it's used to enable large file
support on 32 bit x86 archs). This commit adds it at the beginning
of all .c and .cpp files
Surface creation now specifies the exact format, not only the bit depth
of each surface which is used for rendering.
Additionally we now actually store the surfaces in that format, instead
of converting everything to 32bpp when drawing or e.g. handling palettes.
We now support 16bit format pixmaps as well as the old ones. Including
both 555 and 565 modes.
We drop the palette argument for pixmap construction as it was only
used for black/white anyway.
Canvas creation is simplified so that there is no separate set_mode
state. Canvases are already created in the right mode and never change.
