[PATCH] block/export/fuse.c: fix fuse-lseek on uclibc or musl

[Fabrice Fontaine]

Include linux/fs.h to avoid the following build failure on uclibc or
musl raised since version 6.0.0:

../block/export/fuse.c: In function 'fuse_lseek':
../block/export/fuse.c:641:19: error: 'SEEK_HOLE' undeclared (first use in this 
function)
  641 |     if (whence != SEEK_HOLE && whence != SEEK_DATA) {
      |                   ^~~~~~~~~
../block/export/fuse.c:641:19: note: each undeclared identifier is reported 
only once for each function it appears in
../block/export/fuse.c:641:42: error: 'SEEK_DATA' undeclared (first use in this 
function); did you mean 'SEEK_SET'?
  641 |     if (whence != SEEK_HOLE && whence != SEEK_DATA) {
      |                                          ^~~~~~~~~
      |                                          SEEK_SET

Fixes:
 - 
http://autobuild.buildroot.org/results/33c90ebf04997f4d3557cfa66abc9cf9a3076137

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
---
 block/export/fuse.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/block/export/fuse.c b/block/export/fuse.c
index fc7b07d2b5..2e3bf8270b 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -31,6 +31,9 @@
 #include <fuse.h>
 #include <fuse_lowlevel.h>
 
+#ifdef __linux__
+#include <linux/fs.h>
+#endif
 
 /* Prevent overly long bounce buffer allocations */
 #define FUSE_MAX_BOUNCE_BYTES (MIN(BDRV_REQUEST_MAX_BYTES, 64 * 1024 * 1024))
-- 
2.32.0