winedump: Add a default case to numeric_leaf().

This addresses two warnings issues by GCC 10 (currently in development
stage 4, so this is unlikely to change):

msc.c:687:9: warning: 'value' may be used uninitialized in this function
msc.c:301:13: warning: 'value' may be used uninitialized in this function

Signed-off-by: Gerald Pfeifer <gerald@pfeifer.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
(cherry picked from commit 7299735fdf)
Signed-off-by: Michael Stefaniuc <mstefani@winehq.org>

tools/winedump/msc.c

@@ -206,6 +206,7 @@ static int numeric_leaf(int* value, const unsigned short int* leaf)
     {
     case fv_integer: *value = fv.v.i; break;
     case fv_longlong: *value = (unsigned)fv.v.llu; printf("bad conversion\n"); break;
+    default: assert( 0 ); *value = 0;
     }
     return len;
 }