[compiler-rt] Only build SME ABI routines for baremetal or platforms that have sys/auxv.h (llvm#69423)

This avoids link failures on other platorms that don't (yet) have an
implementation of __aarch64_sme_accessible.

Author: sdesmalen-arm

compiler-rt/lib/builtins/CMakeLists.txt

@@ -555,8 +555,9 @@ set(aarch64_SOURCES
   aarch64/fp_mode.c
 )
 
-if(COMPILER_RT_HAS_ASM_SME)
+if(COMPILER_RT_HAS_ASM_SME AND (COMPILER_RT_HAS_AUXV OR COMPILER_RT_BAREMETAL_BUILD))
   list(APPEND aarch64_SOURCES aarch64/sme-abi.S aarch64/sme-abi-init.c)
+  message(STATUS "AArch64 SME ABI routines enabled")
 else()
   message(STATUS "AArch64 SME ABI routines disabled")
 endif()