Merge bitcoin/bitcoin#25051: Bugfix: configure: Define defaults for enable_arm_{crc,shani}

7fd0860 Bugfix: configure: Define defaults for enable_arm_{crc,shani} (Luke Dashjr)

Pull request description:

  Fix for #17398 and #24115

  Trivial, mostly for consistency (you'd have to *try* to break this)

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Tree-SHA512: 51c389787c369f431ca57071f03392438bff9fd41f128c63ce74ca30d2257213f8be225efcb5c1329ad80b714f44427d721215d4f848cc8e63060fa5bc8f1f2e

Author: laanwj

configure.ac

@@ -470,6 +470,8 @@ fi
 dnl Don't allow extended (non-ASCII) symbols in identifiers. This is easier for code review.
 AX_CHECK_COMPILE_FLAG([-fno-extended-identifiers], [CORE_CXXFLAGS="$CORE_CXXFLAGS -fno-extended-identifiers"], [], [$CXXFLAG_WERROR])
 
+enable_arm_crc=no
+enable_arm_shani=no
 enable_sse42=no
 enable_sse41=no
 enable_avx2=no