IntelFrameworkModulePkg: SerialStatusCode output was incorrect

The string being built had a character being overwritten.  This
also lead to a NULL character being sent out to the serial port
for the last character in the string.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9669 6f19259b-4bc3-4df7-8a09-765794883524
2 files changed