docs: fix capitalization in doxygen comments

Change-Id: Ibf5ee5119d12d60d382b0acef8dfd08277c18fcb
diff --git a/tools/ndn-autoconfig/ndn-fch-discovery.cpp b/tools/ndn-autoconfig/ndn-fch-discovery.cpp
index c6df1b7..52521e7 100644
--- a/tools/ndn-autoconfig/ndn-fch-discovery.cpp
+++ b/tools/ndn-autoconfig/ndn-fch-discovery.cpp
@@ -127,11 +127,7 @@
 class HttpException : public std::runtime_error
 {
 public:
-  explicit
-  HttpException(const std::string& what)
-    : std::runtime_error(what)
-  {
-  }
+  using std::runtime_error::runtime_error;
 };
 
 NdnFchDiscovery::NdnFchDiscovery(const std::string& url)