Strip trailing '\n' from error_report()'s first argument

error_report() prepends location, and appends a newline.  The message
constructed from the arguments should not contain a newline.  Fix the
obvious offenders.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

qemu-error.c

@@ -193,6 +193,8 @@ void error_print_loc(void)
 
 /*
  * Print an error message to current monitor if we have one, else to stderr.
+ * Format arguments like sprintf().  The result should not contain
+ * newlines.
  * Prepend the current location and append a newline.
  * It's wrong to call this in a QMP monitor.  Use qerror_report() there.
  */