deps: update llhttp to 2.1.4

Refs: https://hackerone.com/reports/1238099
Refs: https://hackerone.com/reports/1238709
Refs: nodejs-private/llhttp-private#7
Refs: nodejs-private/llhttp-private#8
CVE-ID: CVE-2021-22959
CVE-ID: CVE-2021-22960

PR-URL: nodejs-private/node-private#285
Reviewed-By: Beth Griggs <bgriggs@redhat.com>

deps/llhttp/README.md

@@ -22,7 +22,7 @@ were tried. However, all of them failed due to resulting significant performance
 degradation.
 
 This project is a port of [http_parser][0] to TypeScript. [llparse][1] is used
-to generate the output C source file, which could be compiled and
+to generate the output C and/or bitcode artifacts, which could be compiled and
 linked with the embedder's program (like [Node.js][7]).
 
 ## Performance
@@ -31,7 +31,7 @@ So far llhttp outperforms http_parser:
 
 |                 | input size |  bandwidth   |  reqs/sec  |   time  |
 |:----------------|-----------:|-------------:|-----------:|--------:|
-| **llhttp**      | 8192.00 mb | 1777.24 mb/s | 3583799.39 ops/sec | 4.61 s |
+| **llhttp** _(C)_ | 8192.00 mb | 1777.24 mb/s | 3583799.39 ops/sec | 4.61 s |
 | **http_parser** | 8192.00 mb | 694.66 mb/s | 1406180.33 req/sec | 11.79 s |
 
 llhttp is faster by approximately **156%**.

deps/llhttp/include/llhttp.h

@@ -3,7 +3,7 @@
 
 #define LLHTTP_VERSION_MAJOR 2
 #define LLHTTP_VERSION_MINOR 1
-#define LLHTTP_VERSION_PATCH 3
+#define LLHTTP_VERSION_PATCH 4
 
 #ifndef LLHTTP_STRICT_MODE
 # define LLHTTP_STRICT_MODE 0