qga: Fix undefined C behavior
The QAPI struct GuestFileWhence has a comment about how we are
exploiting equivalent values between two different integer types
shared in a union. But C says behavior is undefined on assignments to
overlapping storage when the two types are not the same width, and
indeed, 'int64_t value' and 'enum QGASeek name' are very likely to be
different in width. Utilize a temporary variable to fix things.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Fixes:
0b4b49387
Fixes: Coverity CID
1421990
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>