Simplify pthreads + dylink warning. NFC (#25638)

Author: sbc100

test/test_other.py

@@ -2243,7 +2243,7 @@ def test_dylink_pthread_static_data(self):
 
   def test_dylink_pthread_warning(self):
     err = self.expect_fail([EMCC, '-Werror', '-sMAIN_MODULE', '-pthread', test_file('hello_world.c')])
-    self.assertContained('error: -sMAIN_MODULE + pthreads is experimental', err)
+    self.assertContained('error: dynamic linking + pthreads is experimental', err)
 
   @node_pthreads
   def test_dylink_pthread_em_asm(self):

tools/link.py

@@ -522,14 +522,9 @@ def get_worker_js_suffix():
 
 
 def setup_pthreads():
-  if settings.RELOCATABLE:
-    # pthreads + dynamic linking has certain limitations
-    if settings.SIDE_MODULE:
-      diagnostics.warning('experimental', '-sSIDE_MODULE + pthreads is experimental')
-    elif settings.MAIN_MODULE:
-      diagnostics.warning('experimental', '-sMAIN_MODULE + pthreads is experimental')
-    elif settings.LINKABLE:
-      diagnostics.warning('experimental', '-sLINKABLE + pthreads is experimental')
+  # pthreads + dynamic linking has certain limitations
+  if settings.SIDE_MODULE or settings.MAIN_MODULE or settings.RELOCATABLE:
+    diagnostics.warning('experimental', 'dynamic linking + pthreads is experimental')
   if settings.ALLOW_MEMORY_GROWTH and not settings.GROWABLE_ARRAYBUFFERS:
     diagnostics.warning('pthreads-mem-growth', '-pthread + ALLOW_MEMORY_GROWTH may run non-wasm code slowly, see https://github.com/WebAssembly/design/issues/1271')