[ur] fix minor coverity issues

Author: Damian Duy

test/conformance/source/environment.cpp

@@ -195,7 +195,7 @@ void DevicesEnvironment::TearDown() {
 KernelsEnvironment *KernelsEnvironment::instance = nullptr;
 
 KernelsEnvironment::KernelsEnvironment(int argc, char **argv,
-                                       std::string kernels_default_dir)
+                                       const std::string &kernels_default_dir)
     : DevicesEnvironment(argc, argv),
       kernel_options(parseKernelOptions(argc, argv, kernels_default_dir)) {
     instance = this;
@@ -206,7 +206,7 @@ KernelsEnvironment::KernelsEnvironment(int argc, char **argv,
 
 KernelsEnvironment::KernelOptions
 KernelsEnvironment::parseKernelOptions(int argc, char **argv,
-                                       std::string kernels_default_dir) {
+                                       const std::string &kernels_default_dir) {
     KernelOptions options;
     for (int argi = 1; argi < argc; ++argi) {
         const char *arg = argv[argi];

test/conformance/testing/include/uur/environment.h

@@ -52,7 +52,8 @@ struct KernelsEnvironment : DevicesEnvironment {
         std::string kernel_directory;
     };
 
-    KernelsEnvironment(int argc, char **argv, std::string kernels_default_dir);
+    KernelsEnvironment(int argc, char **argv,
+                       const std::string &kernels_default_dir);
     virtual ~KernelsEnvironment() override = default;
 
     virtual void SetUp() override;
@@ -65,7 +66,7 @@ struct KernelsEnvironment : DevicesEnvironment {
 
   private:
     KernelOptions parseKernelOptions(int argc, char **argv,
-                                     std::string kernels_default_dir);
+                                     const std::string &kernels_default_dir);
     std::string getKernelSourcePath(const std::string &kernel_name,
                                     uint32_t device_index);
     std::string getSupportedILPostfix(uint32_t device_index);