arm64/asm: Remove unused enable_da macro

We no longer use the enable_da macro, remove it to avoid having to think
about maintaining it.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221019120346.72289-1-broonie@kernel.orgSigned-off-by: Will Deacon <will@kernel.org>

arch/arm64/include/asm/assembler.h

@@ -51,11 +51,6 @@
 	msr	daif, \flags
 	.endm
 
-	/* IRQ/FIQ are the lowest priority flags, unconditionally unmask the rest. */
-	.macro enable_da
-	msr	daifclr, #(8 | 4)
-	.endm
-
 /*
  * Save/restore interrupts.
  */