StdLib/LibC/Uefi/Devices/Console/daConsole.c: Fix bug where unconvertable wide chara...

StdLib/LibC/Uefi/Devices/Console/daConsole.c:  Fix bug where unconvertable wide characters would cause the code to hang or generate an exception.

When the WideTtyCvt() function encountered an unconvertable character, it properly replaced it but did not update the byte count, numB, to 1 and instead left it at -1.

This fix sets numB to 1 when an unconvertable character is replaced.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: tim.lewis@insidesw.com
Reviewed-by: daryl.mcdaniel@intel.com
Reviewed-by: erik.c.bjorge@intel.com
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13540 6f19259b-4bc3-4df7-8a09-765794883524