test: add unit tests for static helpers in fabrics.c

Adds libnvme/test/test-fabrics.c, which tests the static helper
functions in src/nvme/fabrics.c without modifying any production source.

The technique is to define 'static' to nothing and then #include the
source file directly.  This exposes all translation-unit-local symbols
in the test binary.  No #ifdef UNIT_TEST guards or visibility changes
are needed — the production files are left completely untouched.

Functions covered:
  strchomp, hostid_from_hostnqn, __add_bool_argument,
  __add_hex_argument, __add_int_argument,
  __add_int_or_minus_one_argument, __add_argument,
  inet4_pton, inet_pton_with_scope, traddr_is_hostname, unescape_uri

The test is gated on want_fabrics in meson.build, matching the
conditional that guards the uriparser test above it.

Signed-off-by: Martin Belanger <[email protected]>

Author: Martin Belanger

libnvme/test/meson.build

@@ -126,7 +126,26 @@ if want_fabrics
         ],
     )
 
-test('libnvme - uriparser', uriparser)
+    test('libnvme - uriparser', uriparser)
+
+    test_fabrics = executable(
+        'test-fabrics',
+        ['test-fabrics.c'],
+        # -fgnu89-inline: '#define static' (used to expose static helpers
+        # for unit testing) turns 'static inline' into plain 'inline'.
+        # Under C99, plain 'inline' has external linkage and may require an
+        # external symbol definition that doesn't exist for header-only
+        # inline functions.  GNU89 semantics treat it as an inlining hint
+        # only, avoiding the linker failure in -static builds.
+        c_args: ['-fgnu89-inline'],
+        dependencies: [
+            config_dep,
+            ccan_dep,
+            libnvme_test_dep,
+        ],
+    )
+
+    test('libnvme - fabrics', test_fabrics)
 endif
 
 if conf.get('HAVE_NETDB')