debug: move all of the debug bits out of the spl

Pull all of the internal debug infrastructure up in to the zfs
code to clean up the layering.  Remove all the dodgy usage of
SET_ERROR and DTRACE_PROBE from the spl.  Luckily it was
lightly used in the spl layer so we're not losing much.

Sponsored-by: https://despairlabs.com/sponsor/
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #17861

include/os/linux/spl/sys/sysmacros.h

@@ -34,11 +34,6 @@
 #include <sys/signal.h>
 #include <asm/page.h>
 
-
-#ifndef _KERNEL
-#define	_KERNEL				__KERNEL__
-#endif
-
 #define	FALSE				0
 #define	TRUE				1
 
@@ -202,9 +197,6 @@ makedev(unsigned int major, unsigned int minor)
 #define	P2SAMEHIGHBIT_TYPED(x, y, type) \
 	(((type)(x) ^ (type)(y)) < ((type)(x) & (type)(y)))
 
-#define	SET_ERROR(err) \
-	(__set_error(__FILE__, __func__, __LINE__, err), err)
-
 #include <linux/sort.h>
 #define	qsort(base, num, size, cmp)		\
 	sort(base, num, size, cmp, NULL)