[PATCH man-pages v2] mremap.2: Update information about MREMAP_DONTUNMAP restrictions

[Alex Henrie <alexhenrie24@gmail.com>]

Link: <https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a4609387859f0281951f5e476d9f76d7fb9ab321>
Signed-off-by: Alex Henrie <alexhenrie24@gmail.com>
---
Changes in v2:
- Move link to Link line in commit message
- Consistently position the word "only"
- Use .B instead of .BR for a word followed by a space

Thanks to Alejandro for your feedback.
---
 man/man2/mremap.2 | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/man/man2/mremap.2 b/man/man2/mremap.2
index 53e0bcf2d..62bf17b76 100644
--- a/man/man2/mremap.2
+++ b/man/man2/mremap.2
@@ -106,7 +106,13 @@ remaps a mapping to a new address but does not unmap the mapping at
 .IP
 The
 .B MREMAP_DONTUNMAP
-flag can be used only with private anonymous mappings
+flag can be used only with mappings that are not
+.B VM_DONTEXPAND
+or
+.BR VM_MIXEDMAP .
+Before Linux 5.13, the
+.B MREMAP_DONTUNMAP
+flag could be used only with private anonymous mappings
 (see the description of
 .B MAP_PRIVATE
 and
-- 
2.47.0