locking, arch/ia64: Reduce <asm/smp.h> header dependencies by moving XTP bits into the new <asm/xtp.h> header

We want to remove the #include <asm/io.h> from <asm/smp.h>, but for this
we have to move the XTP bits into a separate header first (as these bits
rely on <asm/io.h> definitions), and include them in the .c files that rely
on those APIs.

Co-developed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/ia64/kernel/iosapic.c

@@ -95,6 +95,7 @@
 #include <asm/iosapic.h>
 #include <asm/processor.h>
 #include <asm/ptrace.h>
+#include <asm/xtp.h>
 
 #undef DEBUG_INTERRUPT_ROUTING
 

arch/ia64/kernel/irq.c

@@ -25,6 +25,7 @@
 #include <linux/kernel_stat.h>
 
 #include <asm/mca.h>
+#include <asm/xtp.h>
 
 /*
  * 'what should we do if we get a hw irq event on an illegal vector'.

arch/ia64/kernel/process.c

@@ -48,6 +48,7 @@
 #include <linux/uaccess.h>
 #include <asm/unwind.h>
 #include <asm/user.h>
+#include <asm/xtp.h>
 
 #include "entry.h"
 

arch/ia64/kernel/sal.c

@@ -18,6 +18,7 @@
 #include <asm/page.h>
 #include <asm/sal.h>
 #include <asm/pal.h>
+#include <asm/xtp.h>
 
  __cacheline_aligned DEFINE_SPINLOCK(sal_lock);
 unsigned long sal_platform_features;

arch/ia64/kernel/setup.c

@@ -65,6 +65,7 @@
 #include <asm/tlbflush.h>
 #include <asm/unistd.h>
 #include <asm/uv/uv.h>
+#include <asm/xtp.h>
 
 #if defined(CONFIG_SMP) && (IA64_CPU_SIZE > PAGE_SIZE)
 # error "struct cpuinfo_ia64 too big!"

arch/ia64/kernel/smp.c

@@ -46,6 +46,7 @@
 #include <asm/tlbflush.h>
 #include <asm/unistd.h>
 #include <asm/mca.h>
+#include <asm/xtp.h>
 
 /*
  * Note: alignment of 4 entries/cacheline was empirically determined