Use explicit .c_str() for hidl_string

am: cfcdceaa4f

Change-Id: Ief21c8e31a1bbd3e389f70a0c9cfe0b837aece35

libwvdrmengine/mediacrypto/src_hidl/WVCryptoPlugin.cpp

@@ -56,7 +56,7 @@ WVCryptoPlugin::WVCryptoPlugin(const void* data, size_t size,
 
 Return<bool> WVCryptoPlugin::requiresSecureDecoderComponent(
     const hidl_string& mime) {
-  if (!strncasecmp(mime, "video/", 6)) {
+  if (!strncasecmp(mime.c_str(), "video/", 6)) {
     // Type is video, so query CDM to see if we require a secure decoder.
     CdmQueryMap status;