wifi: Change namespace

Move the implementation to "android::hardware::wifi:V1_0::implementation"
namespace.
This is following the style guidelines in NFC HIDL
implementation(go/aog/279421).

While there,
Run checkstyle to correct formatting issues.

Bug:31936700
Test: mmma -j32 hardware/interfaces/wifi/1.0/default
Change-Id: I5600a60a0041b3318ed9289823ec335a8ed8a83d
diff --git a/wifi/1.0/default/failure_reason_util.h b/wifi/1.0/default/failure_reason_util.h
index d731700..7d51bbf 100644
--- a/wifi/1.0/default/failure_reason_util.h
+++ b/wifi/1.0/default/failure_reason_util.h
@@ -23,14 +23,18 @@
 namespace android {
 namespace hardware {
 namespace wifi {
+namespace V1_0 {
+namespace implementation {
 
 std::string LegacyErrorToString(wifi_error error);
 
-V1_0::FailureReason CreateFailureReason(
-    V1_0::CommandFailureReason reason, const std::string& description);
-V1_0::FailureReason CreateFailureReasonLegacyError(
-    wifi_error error, const std::string& description);
+FailureReason CreateFailureReason(CommandFailureReason reason,
+                                  const std::string& description);
+FailureReason CreateFailureReasonLegacyError(wifi_error error,
+                                             const std::string& description);
 
+}  // namespace implementation
+}  // namespace V1_0
 }  // namespace wifi
 }  // namespace hardware
 }  // namespace android