Remove ARM udf and dbg intrinsics

These have already been removed for AArch64

Author: Amanieu

crates/core_arch/src/arm/mod.rs

@@ -68,35 +68,3 @@ pub(crate) mod neon;
 #[cfg(target_endian = "little")]
 #[cfg(any(target_feature = "v7", doc))]
 pub use neon::*;
-
-/// Generates the trap instruction `UDF`
-#[cfg(target_arch = "arm")]
-#[cfg_attr(test, assert_instr(udf))]
-#[inline]
-pub unsafe fn udf() -> ! {
-    crate::intrinsics::abort()
-}
-
-/// Generates a DBG instruction.
-///
-/// This provides a hint to debugging and related systems. The argument must be
-/// a constant integer from 0 to 15 inclusive. See implementation documentation
-/// for the effect (if any) of this instruction and the meaning of the
-/// argument. This is available only when compiling for AArch32.
-// Section 10.1 of ACLE says that the supported arches are: 7, 7-M
-// "The DBG hint instruction is added in ARMv7. It is UNDEFINED in the ARMv6 base architecture, and
-// executes as a NOP instruction in ARMv6K and ARMv6T2." - ARM Architecture Reference Manual ARMv7-A
-// and ARMv7-R edition (ARM DDI 0406C.c) sections D12.4.1 "ARM instruction set support" and D12.4.2
-// "Thumb instruction set support"
-#[cfg(any(target_feature = "v7", doc))]
-#[inline(always)]
-#[rustc_legacy_const_generics(0)]
-pub unsafe fn __dbg<const IMM4: i32>() {
-    static_assert_uimm_bits!(IMM4, 4);
-    dbg(IMM4);
-}
-
-extern "unadjusted" {
-    #[link_name = "llvm.arm.dbg"]
-    fn dbg(_: i32);
-}