vulkaninfo: updated json documentation

Currently, the json option doesn't specify that it only outputs for one
gpu and that it follows a schema. This rectifies that.

file changed
 - vulkaninfo/vulkaninfo.cpp

Change-Id: I3af8d559b2464d7ce00ce21e58a1c3054c0740b4

1 files changed, 2 insertions, 2 deletions

diff --git a/vulkaninfo/vulkaninfo.cpp b/vulkaninfo/vulkaninfo.cpp
index 1cd35c06..de1bd973 100644
--- a/vulkaninfo/vulkaninfo.cpp
+++ b/vulkaninfo/vulkaninfo.cpp
@@ -619,8 +619,8 @@ void print_usage(const char *argv0) {
     std::cout << "--html                Produce an html version of vulkaninfo output, saved as\n";
     std::cout << "                      \"vulkaninfo.html\" in the directory in which the command is\n";
     std::cout << "                      run.\n";
-    std::cout << "-j, --json            Produce a json version of vulkaninfo output to standard\n";
-    std::cout << "                      output.\n";
+    std::cout << "-j, --json            Produce a json version of vulkaninfo to standard output of the\n";
+    std::cout << "                      first gpu in the system conforming to the DevSim schema.\n";
     std::cout << "--json=<gpu-number>   For a multi-gpu system, a single gpu can be targetted by\n";
     std::cout << "                      specifying the gpu-number associated with the gpu of \n";
     std::cout << "                      interest. This number can be determined by running\n";