[SYCL] Fix some incorrect diagnostic wording; NFC (#3705)

Author: AaronBallman

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -11328,7 +11328,7 @@ def warn_sycl_kernel_too_big_args : Warning<
   "size of kernel arguments (%0 bytes) may exceed the supported maximum "
   "of %1 bytes on some devices">, InGroup<SyclStrict>, ShowInSystemHeader;
 def err_sycl_virtual_types : Error<
-  "No class with a vtable can be used in a SYCL kernel or any code included in the kernel">;
+  "no class with a vtable can be used in a SYCL kernel or any code included in the kernel">;
 def note_sycl_recursive_function_declared_here: Note<"function implemented using recursion declared here">;
 def err_sycl_non_trivially_copy_ctor_dtor_type
     : Error<"kernel parameter has non-trivially %select{copy "
@@ -11349,7 +11349,7 @@ def err_sycl_attribute_internal_function
     : Error<"%0 attribute cannot be applied to a "
             "static function or function in an anonymous namespace">;
 def err_sycl_compiletime_property_duplication : Error<
-  "Can't apply %0 property twice to the same accessor">;
+  "can't apply %0 property twice to the same accessor">;
 def err_sycl_invalid_property_list_param_number : Error<
   "%0 must have exactly one template parameter">;
 def err_sycl_invalid_accessor_property_template_param : Error<
@@ -11363,10 +11363,10 @@ def err_sycl_num_kernel_wrong_reqd_wg_size : Error<
   "%0 attribute must evenly divide the work-group size for the %1 attribute">;
 
 def warn_sycl_pass_by_value_deprecated 
-    : Warning<"Passing kernel functions by value is deprecated in SYCL 2020">,
+    : Warning<"passing kernel functions by value is deprecated in SYCL 2020">,
       InGroup<Sycl2020Compat>, ShowInSystemHeader;
 def warn_sycl_pass_by_reference_future 
-    : Warning<"Passing of kernel functions by reference is a SYCL 2020 extension">,
+    : Warning<"passing of kernel functions by reference is a SYCL 2020 extension">,
       InGroup<Sycl2017Compat>, ShowInSystemHeader;
 def warn_sycl_implicit_decl
     : Warning<"SYCL 1.2.1 specification requires an explicit forward "

clang/test/CodeGenSYCL/kernel-by-reference.cpp

@@ -15,15 +15,15 @@ int simple_add(int i) {
 int main() {
   queue q;
 #if defined(SYCL2020)
-  // expected-warning@#KernelSingleTask2017 {{Passing kernel functions by value is deprecated in SYCL 2020}}
+  // expected-warning@#KernelSingleTask2017 {{passing kernel functions by value is deprecated in SYCL 2020}}
   // expected-note@+3 {{in instantiation of function template specialization}}
 #endif
   q.submit([&](handler &h) {
     h.single_task_2017<class sycl2017>([]() { simple_add(10); });
   });
 
 #if defined(SYCL2017)
-  // expected-warning@#KernelSingleTask {{Passing of kernel functions by reference is a SYCL 2020 extension}}
+  // expected-warning@#KernelSingleTask {{passing of kernel functions by reference is a SYCL 2020 extension}}
   // expected-note@+3 {{in instantiation of function template specialization}}
 #endif
   q.submit([&](handler &h) {

clang/test/SemaSYCL/buffer_location.cpp

@@ -86,7 +86,7 @@ int main() {
         accessorD.use();
         //expected-error@+1{{sixth template parameter of the accessor must be of accessor_property_list type}}
         accessorE.use();
-        //expected-error@+1{{Can't apply buffer_location property twice to the same accessor}}
+        //expected-error@+1{{can't apply buffer_location property twice to the same accessor}}
         accessorF.use();
 #endif
       });