[musl] [PATCH v2] posix_fallocate.3: add EOPNOTSUPP error code.

["Érico Rolim" <erico.erc@gmail.com>]

As can be seen in

https://git.musl-libc.org/cgit/musl/tree/src/fcntl/posix_fallocate.c?id=73cc775bee53300c7cf759f37580220b18ac13d3

musl libc returns the syscall's errors directly, which means it doesn't
perform the same emulation as glibc, and can return EOPNOTSUPP to an
application, which isnt't listed in ERRORS.
---

This patch replaces "[patch] posix_fallocate.3: add note about error
codes for musl." from
https://lore.kernel.org/linux-man/CAFDeuWPmWWHatxnZ9HsYN2fp3gagHOKCsKmVDj0F6us9XWKwFQ@mail.gmail.com/T/#t

posix_fallocate(3p) doesn't list EOPNOTSUPP as an error that can be
returned to applications. Should it be noted in the man page that this
is something added/required by Linux? (I might be mistaken regarding
this assumption).

 man3/posix_fallocate.3 | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/man3/posix_fallocate.3 b/man3/posix_fallocate.3
index 58338d673..125bcc12b 100644
--- a/man3/posix_fallocate.3
+++ b/man3/posix_fallocate.3
@@ -98,6 +98,13 @@ There is not enough space left on the device
containing the file
 referred to by
 .IR fd .
 .TP
+.B EOPNOTSUPP
+The filesystem containing the file referred to by
+.IR fd
+does not support this operation.
+This error code can be returned by libc's that don't perform the
+emulation shown in NOTES, such as musl libc.
+.TP
 .B ESPIPE
 .I fd
 refers to a pipe.
-- 
2.28.0