Fix use of uninitialized stat result in POSIX RemoveFileNative

When stat() failed with an errno other than ENOENT the code dropped
out of the error check and then read Stat.st_mode from a struct that
was never populated. IsFileModeReadOnly() therefore inspected
uninitialized stack memory, which could randomly classify the target
as read-only and fail the removal with EACCES, or classify a real
read-only file as writable and corrupt the caller's expectation that
ForceRemoveReadOnlyFiles=false guards them.

Restructure the branches so the mode check only runs when stat()
succeeded, ENOENT continues to short-circuit with a cleared error,
and any other stat() failure falls through to std::filesystem::remove
which will surface the actual OS error via Ec.

0 files changed, 0 insertions, 0 deletions