meson: static lib for utils and settings

`settings.cpp` and `utils.cpp` were compiled multiple times for various
binaries. Create static libraries to compile them once.

Tested: Code compiles.

Change-Id: I0827f44ff6274cf131fb91431af982a4a6eeee6a
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>
diff --git a/test/meson.build b/test/meson.build
index ef56b48..51496ac 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -17,7 +17,6 @@
         'test_systemd_signal',
         'systemd_signal.cpp',
         '../systemd_target_signal.cpp',
-        '../utils.cpp',
         dependencies: [
             gtest,
             libgpiod,
@@ -26,6 +25,7 @@
             sdbusplus,
             sdeventplus,
         ],
+        link_with: [utils_lib],
         implicit_include_directories: true,
         include_directories: '../',
     ),
@@ -37,7 +37,6 @@
         'test_scheduled_host_transition',
         'test_scheduled_host_transition.cpp',
         '../scheduled_host_transition.cpp',
-        '../utils.cpp',
         dependencies: [
             cereal,
             gmock,
@@ -47,6 +46,7 @@
             sdbusplus,
             sdeventplus,
         ],
+        link_with: [utils_lib],
         implicit_include_directories: true,
         include_directories: '../',
     ),