BaseTools:Updata the output encoding of the Popen function

BZ:https://bugzilla.tianocore.org/show_bug.cgi?id=2015

Not all output works in utf-8, so change the encoding to
the default

This patch is going to fix that issue.

Cc: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Zhiju.Fan <zhijux.fan@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

BaseTools/Source/Python/Pkcs7Sign/Pkcs7Sign.py

@@ -116,7 +116,7 @@ if __name__ == '__main__':
   if Process.returncode != 0:
     print('ERROR: Open SSL command not available.  Please verify PATH or set OPENSSL_PATH')
     sys.exit(Process.returncode)
-  print(Version[0].decode(encoding='utf-8', errors='ignore'))
+  print(Version[0].decode())
 
   #
   # Read input file into a buffer and save input filename