build: fix case of project language name

[ upstream commit f6da046a1528895a96e1fbb7deef2c668efd0a56 ]

According to the meson manual [1], the project language should be given
as 'c', rather than 'C' in the initial "project" function call. While
meson itself does not complain about this, the "muon" project, which
attempts to re-implement meson in C, does complain.

/home/bruce/dpdk/meson.build:4:17: error 'C' is not a valid language
  4 | project('DPDK', 'C',
                      ^

[1] https://mesonbuild.com/Reference-manual_functions.html#project

Fixes: a25a650 ("build: add infrastructure for meson and ninja builds")

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Reviewed-by: Tyler Retzlaff <roretzla@linux.microsoft.com>

meson.build

@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright(c) 2017-2019 Intel Corporation
 
-project('DPDK', 'C',
+project('DPDK', 'c',
         # Get version number from file.
         # Fallback to "more" for Windows compatibility.
         version: run_command(find_program('cat', 'more'),