Disable nlohmann exceptions

Nlohmann json gives the option to disable exceptions through a flag
documented here: https://json.nlohmann.me/home/exceptions/

While we don't really use nlohmann exceptions in practice, disabling
this flag saves us about 5k in compressed binary size, for probably no
impact.

Tested:
Code compiles, binary size change seen locally.

redfishtool -S Always -A Session -u root -p 0penBmc -vvvvvvvvv -r 192.168.7.2 raw GET /redfish/v1/Managers/bmc

Returns the managers resource.  Given that it both parses and encodes
json, that would prove that nlohmann is working properly.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: I68cba1628434d050379daca9bc39e4c3d724012b
diff --git a/meson.build b/meson.build
index b2b8c90..f343272 100644
--- a/meson.build
+++ b/meson.build
@@ -273,7 +273,8 @@
 '-DBOOST_COROUTINES_NO_DEPRECATION_WARNING',
 '-DBOOST_URL_STANDALONE',
 '-DBOOST_URL_HEADER_ONLY',
-'-DBOOST_ALLOW_DEPRECATED_HEADERS'
+'-DBOOST_ALLOW_DEPRECATED_HEADERS',
+'-DJSON_NOEXCEPTION'
 ]),
 language : 'cpp')