Fix another diagnostic for style; NFC

Author: AaronBallman

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -3975,7 +3975,7 @@ def warn_acquired_before : Warning<
   "%0 '%1' must be acquired before '%2'">,
   InGroup<ThreadSafetyAnalysis>, DefaultIgnore;
 def warn_acquired_before_after_cycle : Warning<
-  "Cycle in acquired_before/after dependencies, starting with '%0'">,
+  "cycle in acquired_before/after dependencies, starting with '%0'">,
   InGroup<ThreadSafetyAnalysis>, DefaultIgnore;
 
 

clang/test/SemaCXX/warn-thread-safety-analysis.cpp

@@ -5838,12 +5838,12 @@ class Foo5 {
 
 
 class Foo6 {
-  Mutex mu1 ACQUIRED_AFTER(mu3);     // expected-warning {{Cycle in acquired_before/after dependencies, starting with 'mu1'}}
-  Mutex mu2 ACQUIRED_AFTER(mu1);     // expected-warning {{Cycle in acquired_before/after dependencies, starting with 'mu2'}}
-  Mutex mu3 ACQUIRED_AFTER(mu2);     // expected-warning {{Cycle in acquired_before/after dependencies, starting with 'mu3'}}
+  Mutex mu1 ACQUIRED_AFTER(mu3);     // expected-warning {{cycle in acquired_before/after dependencies, starting with 'mu1'}}
+  Mutex mu2 ACQUIRED_AFTER(mu1);     // expected-warning {{cycle in acquired_before/after dependencies, starting with 'mu2'}}
+  Mutex mu3 ACQUIRED_AFTER(mu2);     // expected-warning {{cycle in acquired_before/after dependencies, starting with 'mu3'}}
 
-  Mutex mu_b ACQUIRED_BEFORE(mu_b);  // expected-warning {{Cycle in acquired_before/after dependencies, starting with 'mu_b'}}
-  Mutex mu_a ACQUIRED_AFTER(mu_a);   // expected-warning {{Cycle in acquired_before/after dependencies, starting with 'mu_a'}}
+  Mutex mu_b ACQUIRED_BEFORE(mu_b);  // expected-warning {{cycle in acquired_before/after dependencies, starting with 'mu_b'}}
+  Mutex mu_a ACQUIRED_AFTER(mu_a);   // expected-warning {{cycle in acquired_before/after dependencies, starting with 'mu_a'}}
 
   void test0() {
     mu_a.Lock();