Linux: capture both stdout and stderr in popen call to avoid printing anything

If an error happens, error message will be read from popen pipe and so
libpcsclite.so will not be found. This is the same outcome as when
stdout is empty.

src/Common/SCardLoader.cpp

@@ -82,9 +82,9 @@ namespace VeraCrypt
 		string pcscPath = "";
 		FILE* pipe = 
 #ifdef TC_LINUX
-			popen("ldconfig -p", "r");
+			popen("ldconfig -p 2>&1", "r");
 #else
-			popen("ldconfig -r", "r"); // FreeBSD
+			popen("ldconfig -r 2>&1", "r"); // FreeBSD
 #endif
 		if (pipe)
 		{