Fix the build on clang-11

Clang tidy 11 got some really neat checks that do a much better job.
Unfortunately, this, combined with the change in how std::executors has
defined how callbacks should work differently in the past, which we
picked up in 1.73, and now in theory we have recursion in a bunch of our
IO loops that we have to break manually.  In practice, this is unlikely
to matter, as there's almost a 0% chance that we go through N thousand
requests without ever starving the IO buffer.

Other changes to make this build include:
1. Adding inline on the appropriate places where declared in a header.
2. Removing an Openssl call that did nothing, as the result was
immediately overwritten.
3. Declaring the subproject dependencies as system dependencies, which
silences the clang-tidy checks for those projects.

Tested:
Code builds again, clang-tidy passes

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: Ic11b1002408e8ac19a17a955e9477cac6e0d7504
diff --git a/meson.build b/meson.build
index 48f7691..27f25ec 100644
--- a/meson.build
+++ b/meson.build
@@ -291,6 +291,7 @@
             'subprojects/nlohmann/single_include/nlohmann',
         ]
     )
+    nlohmann_json = nlohmann_json.as_system('system')
 endif
 bmcweb_dependencies += nlohmann_json
 
@@ -299,6 +300,7 @@
   subproject('boost', required: false)
   boost_inc = include_directories('subprojects/boost_1_75_0/', is_system:true)
   boost  = declare_dependency(include_directories : boost_inc)
+  boost = boost.as_system('system')
 endif
 bmcweb_dependencies += boost
 
@@ -308,6 +310,7 @@
   subproject('boost-url', required: false)
   boost_url_inc = include_directories('subprojects/boost-url/include', is_system:true)
   boost_url= declare_dependency(include_directories : boost_url_inc)
+  boost_url = boost_url.as_system('system')
 endif
 bmcweb_dependencies += boost_url
 
@@ -319,6 +322,8 @@
     gtest = gtest_proj.get_variable('gtest_main_dep')
     gmock = gtest_proj.get_variable('gmock_dep')
   endif
+  gtest = gtest.as_system('system')
+  gmock = gmock.as_system('system')
 endif
 
 # Source files