Merge bitcoin/bitcoin#31662: cmake: Do not modify CMAKE_TRY_COMPILE_TARGET_TYPE globally

2c4b229c90 cmake: Introduce `FUZZ_LIBS` (Hennadii Stepanov)
ea929c0848 scripted-diff: Rename CMake helper module (Hennadii Stepanov)
8d238c1dfd cmake: Delete `check_cxx_source_links*` macros (Hennadii Stepanov)
71bf8294a9 cmake: Convert `check_cxx_source_compiles_with_flags` to a function (Hennadii Stepanov)
88ee6800c9 cmake: Delete `check_cxx_source_links_with_flags` macro (Hennadii Stepanov)
09e8fd25b1 build: Don't override CMake's default try_compile target (Hennadii Stepanov)

Pull request description:

  This was requested in https://github.com/bitcoin/bitcoin/pull/31359#issuecomment-2515287092.

  From https://github.com/bitcoin/bitcoin/pull/31359#issuecomment-2511246212:
  > (Almost?) every CMake check internally uses the [`try_compile()`](https://cmake.org/cmake/help/latest/command/try_compile.html) command, whose behaviour, in turn, depends on the [`CMAKE_TRY_COMPILE_TARGET_TYPE`](https://cmake.org/cmake/help/latest/variable/CMAKE_TRY_COMPILE_TARGET_TYPE.html) variable:
  >
  >    1. The default value, `EXECUTABLE`, enables both compiler and linker checks.
  >
  >    2. The `STATIC_LIBRARY` value enables only compiler checks.
  >
  >
  > To mimic Autotools' behaviour, we [disabled](d3f42fa08f/cmake/module/CheckSourceCompilesAndLinks.cmake (L9-L10)) linker checks by setting `CMAKE_TRY_COMPILE_TARGET_TYPE` to `STATIC_LIBRARY` globally (perhaps not the best design). This effectively separates the entire CMake script into regions where `CMAKE_TRY_COMPILE_TARGET_TYPE` is:
  >
  >    * unset
  >
  >    * set to `STATIC_LIBRARY`
  >
  >    * set to `EXECUTABLE`

  From https://github.com/bitcoin/bitcoin/pull/31359#issuecomment-2515287092:
  > > This seems very fragile and unintuitive, and the fact that this could silently break at any point is not documented in any way. I don't think other bad design decisions should lead to us having to write even more boilerplate code to fix things that should "just work" (minus the upstream bugs).
  >
  > Agreed. I forgot that we set `CMAKE_TRY_COMPILE_TARGET_TYPE` globally. And even worse, it's buried in a module. If that upsets CMake internal tests, I think we should undo that.

  This PR ensures that `CMAKE_TRY_COMPILE_TARGET_TYPE` is modified only within local scopes.

  Additionally, the `FUZZ_LIBS` variable has been introduced to handle additional libraries required for linking, rather than link options, in certain build environment, such as OSS-Fuzz.

ACKs for top commit:
  TheCharlatan:
    Re-ACK 2c4b229c90
  theuni:
    utACK 2c4b229c90

Tree-SHA512: f72ffa8f50f216fc1a2f8027ba8ddfd4acd42b94ff6c1cb2138f2da51eb8f945660e97d3c247d7f3f7ec8dfebbccec3ab84347d6ae2e3f8a40f3d7aa8b14cde9

cmake/crc32c.cmake

@@ -7,6 +7,7 @@
 # buildsystem.
 
 include(CheckCXXSourceCompiles)
+include(CheckSourceCompilesWithFlags)
 
 # Check for __builtin_prefetch support in the compiler.
 check_cxx_source_compiles("
@@ -42,7 +43,7 @@ if(MSVC)
 else()
   set(SSE42_CXXFLAGS -msse4.2)
 endif()
-check_cxx_source_compiles_with_flags("${SSE42_CXXFLAGS}" "
+check_cxx_source_compiles_with_flags("
   #include <cstdint>
   #if defined(_MSC_VER)
   #include <intrin.h>
@@ -58,11 +59,12 @@ check_cxx_source_compiles_with_flags("${SSE42_CXXFLAGS}" "
     return l;
   }
   " HAVE_SSE42
+  CXXFLAGS ${SSE42_CXXFLAGS}
 )
 
 # Check for ARMv8 w/ CRC and CRYPTO extensions support in the compiler.
 set(ARM64_CRC_CXXFLAGS -march=armv8-a+crc+crypto)
-check_cxx_source_compiles_with_flags("${ARM64_CRC_CXXFLAGS}" "
+check_cxx_source_compiles_with_flags("
   #include <arm_acle.h>
   #include <arm_neon.h>
 
@@ -76,6 +78,7 @@ check_cxx_source_compiles_with_flags("${ARM64_CRC_CXXFLAGS}" "
     return 0;
   }
   " HAVE_ARM64_CRC32C
+  CXXFLAGS ${ARM64_CRC_CXXFLAGS}
 )
 
 add_library(crc32c STATIC EXCLUDE_FROM_ALL