Merge bitcoin/bitcoin#27580: msvc: Cleanup after upgrading libsecp256k1 up to 0.3.0

d9b54c4 msvc: Cleanup after upgrading libsecp256k1 up to 0.3.0 (Hennadii Stepanov)

Pull request description:

  libsecp256k1 [v0.3.0](https://github.com/bitcoin-core/secp256k1/blob/master/CHANGELOG.md#030---2023-03-08):
  > Removed the configuration header `src/libsecp256k1-config.h`.

  This PR removed the code that has been unused since bitcoin/bitcoin#27230.

  The `USE_ASM_X86_64` is now undefined explicitly (but actually it seems a bit redundant).

  The `ECMULT_GEN_PREC_BITS` and `ECMULT_WINDOW_SIZE` macros are defined by the source code to their defaults.

  ---

  Considering the upcoming CMake-based build system, these changes have a low-priority.

ACKs for top commit:
  fanquake:
    ACK d9b54c4

Tree-SHA512: f279aeee1da57af5fdc4bd4f2000f1fea4180895f0e5b576545092a8318c756d36192f09a0cb0929cef74ed384c46777d5e6b6f92f4542b308e984e4abf473dc

Author: fanquake

build_msvc/libsecp256k1/libsecp256k1.vcxproj

@@ -15,6 +15,7 @@
   <ItemDefinitionGroup>
     <ClCompile>
       <PreprocessorDefinitions>ENABLE_MODULE_RECOVERY;ENABLE_MODULE_EXTRAKEYS;ENABLE_MODULE_SCHNORRSIG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <UndefinePreprocessorDefinitions>USE_ASM_X86_64;%(UndefinePreprocessorDefinitions)</UndefinePreprocessorDefinitions>
       <AdditionalIncludeDirectories>..\..\src\secp256k1;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>4146;4244;4267;4334</DisableSpecificWarnings>
     </ClCompile>

build_msvc/libsecp256k1_config.h

@@ -111,7 +111,6 @@ def main():
         set_properties(vcxproj_filename, '@SOURCE_FILES@\n', content)
     parse_config_into_btc_config()
     copyfile(os.path.join(SOURCE_DIR,'../build_msvc/bitcoin_config.h'), os.path.join(SOURCE_DIR, 'config/bitcoin-config.h'))
-    copyfile(os.path.join(SOURCE_DIR,'../build_msvc/libsecp256k1_config.h'), os.path.join(SOURCE_DIR, 'secp256k1/src/libsecp256k1-config.h'))
 
 if __name__ == '__main__':
     main()