Fix build on ToT Clang

ToT Clang complains about the following error:

frameworks/native/vulkan/vkjson/vkjson.cc:1211:20: error: call to 'ToJsonValue' is ambiguous
 1211 |     object_[key] = ToJsonValue(*value);
      |                    ^~~~~~~~~~~
frameworks/native/vulkan/vkjson/vkjson.cc:1173:20: note: candidate function [with T = char, N = 63]
 1173 | inline Json::Value ToJsonValue(const T (&value)[N]) {
      |                    ^
frameworks/native/vulkan/vkjson/vkjson.cc:1178:20: note: candidate function [with N = 63]
 1178 | inline Json::Value ToJsonValue(const char (&value)[N]) {
      |                    ^

Test: presubmit
Bug: 363682086
Change-Id: Ifa4e8e5df715b1adc99343782a44c8fc302554ae