cmake: Remove ENABLE_ARM_SHANI from bitcoin-build-config.h

`ENABLE_ARM_SHANI` is already conditionally defined for the
`bitcoin_crypto` target, so defining it in `bitcoin-build-config.h` is
redundant.

cmake/bitcoin-build-config.h.in

@@ -29,9 +29,6 @@
 /* Copyright year */
 #define COPYRIGHT_YEAR @COPYRIGHT_YEAR@
 
-/* Define this symbol to build code that uses ARMv8 SHA-NI intrinsics */
-#cmakedefine ENABLE_ARM_SHANI 1
-
 /* Define if external signer support is enabled */
 #cmakedefine ENABLE_EXTERNAL_SIGNER 1
 

cmake/introspection.cmake

@@ -217,5 +217,4 @@ if(NOT MSVC)
     " HAVE_ARM_SHANI
     CXXFLAGS ${ARM_SHANI_CXXFLAGS}
   )
-  set(ENABLE_ARM_SHANI ${HAVE_ARM_SHANI})
 endif()