Merge #14214: convert C-style (void) parameter lists to C++ style ()

3ccfa34b32 convert C-style (void) parameter lists to C++ style () (Arvid Norberg)

Pull request description:

  In C, an empty parameter list, `()`, means the function takes any arguments, and `(void)` means the function does not take any parameters.
  In C++, an empty parameter list means the function does not take any parameters.

  So, C++ still supports `(void)` parameter lists with the same semantics, why change to `()`?

  1. removing the redundant `void` improves signal-to-noise ratio of the code
  2. using `(void)` exposes a rare inconsistency in that a template taking a template `(T)` parameter list, cannot be instantiated with `T=void`

Tree-SHA512: be2897b6c5e474873aa878ed6bac098382cd21866aec33752fe40b089a6331aa6263cae749aba1b4a41e8467f1a47086d32eb74abaf09927fd5a2f44a4b2109a

src/init.cpp

@@ -691,7 +691,7 @@ static void ThreadImport(std::vector<fs::path> vImportFiles)
  *  Ensure that Bitcoin is running in a usable environment with all
  *  necessary library support.
  */
-static bool InitSanityCheck(void)
+static bool InitSanityCheck()
 {
     if(!ECC_InitSanityCheck()) {
         InitError("Elliptic curve cryptography sanity check failure. Aborting.");