arm64: kexec: machine_kexec should call __flush_icache_range

machine_kexec flushes the reboot_code_buffer from the icache
after stopping the other cpus.

Commit 3b8c9f1cdfc5 ("arm64: IPI each CPU after invalidating the I-cache
for kernel mappings") added an IPI call to flush_icache_range, which
causes a hang here, so replace the call with __flush_icache_range

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/kernel/machine_kexec.c

@@ -184,7 +184,7 @@ void machine_kexec(struct kimage *kimage)
 
 	/* Flush the reboot_code_buffer in preparation for its execution. */
 	__flush_dcache_area(reboot_code_buffer, arm64_relocate_new_kernel_size);
-	flush_icache_range((uintptr_t)reboot_code_buffer,
+	__flush_icache_range((uintptr_t)reboot_code_buffer,
 		arm64_relocate_new_kernel_size);
 
 	/* Flush the kimage list and its buffers. */