docs: flex -> Flex

Reviewed-by: Eric Engestrom <eric@engestrom.ch>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6915>
diff --git a/docs/install.rst b/docs/install.rst
index 0ea14b7..f7787fe 100644
--- a/docs/install.rst
+++ b/docs/install.rst
@@ -44,9 +44,9 @@
    module is required. Version 0.8.0 or later should work.
 -  lex / yacc - for building the Mesa IR and GLSL compiler.
 
-   On Linux systems, flex and bison versions 2.5.35 and 2.4.1,
+   On Linux systems, Flex and bison versions 2.5.35 and 2.4.1,
    respectively, (or later) should work. On Windows with MinGW, install
-   flex and bison with:
+   Flex and bison with:
 
    ::
 
@@ -57,7 +57,7 @@
 
 .. note::
 
-   Some versions can be buggy (eg. flex 2.6.2) so do try others
+   Some versions can be buggy (eg. Flex 2.6.2) so do try others
    if things fail.
 
 1.2 Requirements
diff --git a/docs/meson.rst b/docs/meson.rst
index 52c0ec3..457e65d 100644
--- a/docs/meson.rst
+++ b/docs/meson.rst
@@ -51,7 +51,7 @@
 You will need to install Python 3 and Meson as a module using pip. This
 is because we use Python for generating code, and rely on external
 modules (mako). You also need pkg-config (a hard dependency of Meson),
-flex, and bison. The easiest way to install everything you need is with
+Flex, and bison. The easiest way to install everything you need is with
 `chocolatey <https://chocolatey.org/>`__.
 
 .. code-block:: console