ANDROID: fuse: Restore upstream type of bitfields in fuse_args

Commit 88b7179f ("ANDROID: fuse: Move functions in preparation for
fuse-bpf") changed the type of these bitfields from the upstream type of
'bool' to 'int', which causes several warnings with recent versions of
clang:

    /builds/linux/fs/fuse/dir.c:168:19: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
            args->out_argvar = true;
                             ^ ~~~~
    /builds/linux/fs/fuse/dir.c:492:18: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
            args.out_argvar = 1;
                            ^ ~
    /builds/linux/fs/fuse/dir.c:1649:20: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
            ap.args.out_pages = true;
                              ^ ~~~~
    /builds/linux/fs/fuse/dir.c:1650:21: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
            ap.args.out_argvar = true;
                               ^ ~~~~
    /builds/linux/fs/fuse/dir.c:1651:23: error: implicit truncation from 'int' to a one-bit wide bit-field changes value from 1 to -1 [-Werror,-Wsingle-bit-bitfield-constant-conversion]
            ap.args.page_zeroing = true;
                                 ^ ~~~~
    5 errors generated.

When fuse_args was moved back to the internal implementation in commit
9a502396 ("ANDROID: fuse-bpf: Use fuse_bpf_args in uapi"), the type
was not restored. Do so now to fix the warnings and reduce the delta
with upstream.

Bug: 265200230
Change-Id: I4d51f331d842a1faff9a937140f0275130e70d73
Signed-off-by: Nathan Chancellor <nathan@kernel.org>