meta-phosphor: Update nlohmann-json

Update to latest release and fixup recipe to use cmake.

Copy styling from rapidjson in meta-oe as these have basically
the same purpose.

Tested-by: Verified image still built

Change-Id: Ideda911b234ee08abe649db97730d1e087474aae
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/recipes-support/nlohmann-json/nlohmann-json_git.bb b/recipes-support/nlohmann-json/nlohmann-json_git.bb
index bbb63a1..a89b659 100644
--- a/recipes-support/nlohmann-json/nlohmann-json_git.bb
+++ b/recipes-support/nlohmann-json/nlohmann-json_git.bb
@@ -1,18 +1,23 @@
-DESCRIPTION = "JSON for modern C++"
+SUMMARY = "JSON for modern C++"
 HOMEPAGE = "https://nlohmann.github.io/json/"
+SECTION = "libs"
 LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://LICENSE.MIT;md5=9a8ae1c2d606c432a2aa2e2de15be22a"
 
 SRC_URI = "git://github.com/nlohmann/json.git"
 
-ALLOW_EMPTY_${PN} = "1"
+PV = "3.2.0+git${SRCPV}"
 
-PV = "3.1.2+git${SRCPV}"
-
-SRCREV = "183390c10b8ba4aa33934ae593f82f352befefc8"
+SRCREV = "8c20571136f2d5351b379a06ad6591bd980880fe"
 
 S = "${WORKDIR}/git"
-do_install_append(){
-    install -d ${D}${includedir}/nlohmann
-    install -m 644 ${S}/single_include/nlohmann/json.hpp ${D}${includedir}/nlohmann/json.hpp
-}
+
+inherit cmake
+
+EXTRA_OECMAKE += "-DJSON_BuildTests=OFF"
+
+# nlohmann-json is a header only C++ library, so the main package will be empty.
+
+RDEPENDS_${PN}-dev = ""
+
+BBCLASSEXTEND = "native nativesdk"