Keeps all of the floating-point utility functions in their own file to
keep them all together. This also provides a place for other
general-purpose floating-point functions to be added in the future,
which will be necessary when improving the flag-setting within the
interpreter.
Fixes warning:
```
../Source/UnitTests/VideoCommon/VertexLoaderTest.cpp:222:15: error: variable 'f' may be uninitialized when used here [-Werror,-Wconditional-uninitialized]
ExpectOut(f * scale);
^
../Source/UnitTests/VideoCommon/VertexLoaderTest.cpp:198:12: note: initialize the variable 'f' to silence this warning
float f, g;
^
= 0.0
../Source/UnitTests/VideoCommon/VertexLoaderTest.cpp:223:15: error: variable 'g' may be uninitialized when used here [-Werror,-Wconditional-uninitialized]
ExpectOut(g * scale);
^
../Source/UnitTests/VideoCommon/VertexLoaderTest.cpp:198:15: note: initialize the variable 'g' to silence this warning
float f, g;
^
= 0.0
```
They are used to remove the flush amounts, but as we don't
flush anymore on vertex loader changes (only on native
vertex format right now), this optimization is now unneeded.
This will allow us to hard code the frac factors within the
vertex loaders.
videoBuffer -> s_video_buffer
size -> s_video_buffer_write_ptr
g_pVideoData -> g_video_buffer_read_ptr (impl moved to Fifo.cpp)
This eradicates the wonderful use of 'size' as a global name, and makes
it clear that s_video_buffer_write_ptr and g_video_buffer_read_ptr are
the two ends of the FIFO buffer s_video_buffer.
Oh, and remove a useless namespace {}.
Lioncash