[PATCH v2] virtio-net: fix a display for num_buffers

[Jiang Wang <jiang.wang@bytedance.com>]

One of num_buffers does not display correctly in
the html. The _b becomes a subscript b. This will
prevent it from being searched by using keyword num_buffers.

Fix it by adding a field keyword.

Signed-off-by: Jiang Wang <jiang.wang@bytedance.com>
---
v1 -> v2: use field keyword instead of adding an escape char.

 content.tex | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/content.tex b/content.tex
index b72bad0..2f65c60 100644
--- a/content.tex
+++ b/content.tex
@@ -3595,8 +3595,8 @@ \subsubsection{Processing of Incoming Packets}\label{sec:Device Types / Network
 the packet (including the header) is spread over.
 
 If a receive packet is spread over multiple buffers, the device
-MUST use all buffers but the last (i.e. the first $num_buffers -
-1$ buffers) completely up to the full length of each buffer
+MUST use all buffers but the last (i.e. the first \field{num_buffers} -
+1 buffers) completely up to the full length of each buffer
 supplied by the driver.
 
 The device MUST use all buffers used by a single receive
-- 
2.11.0