uml: remove code made redundant by CHOOSE_MODE removal

This patch makes a number of simplifications enabled by the removal of
CHOOSE_MODE.  There were lots of functions that looked like

	int foo(args){
		foo_skas(args);
	}

The bodies of foo_skas are now folded into foo, and their declarations (and
sometimes entire header files) are deleted.

In addition, the union uml_pt_regs, which was a union between the tt and skas
register formats, is now a struct, with the tt-mode arm of the union being
removed.

It turns out that usr2_handler was unused, so it is gone.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/um/os-Linux/skas/trap.c b/arch/um/os-Linux/skas/trap.c
index 3b600c2..d43e470 100644
--- a/arch/um/os-Linux/skas/trap.c
+++ b/arch/um/os-Linux/skas/trap.c
@@ -15,13 +15,13 @@
 #include "sysdep/ptrace_user.h"
 #include "os.h"
 
-static union uml_pt_regs ksig_regs[UM_NR_CPUS];
+static struct uml_pt_regs ksig_regs[UM_NR_CPUS];
 
 void sig_handler_common_skas(int sig, void *sc_ptr)
 {
 	struct sigcontext *sc = sc_ptr;
-	union uml_pt_regs *r;
-	void (*handler)(int, union uml_pt_regs *);
+	struct uml_pt_regs *r;
+	void (*handler)(int, struct uml_pt_regs *);
 	int save_user, save_errno = errno;
 
 	/* This is done because to allow SIGSEGV to be delivered inside a SEGV
@@ -42,12 +42,12 @@
 	}
 	else r = TASK_REGS(get_current());
 
-	save_user = r->skas.is_user;
-	r->skas.is_user = 0;
+	save_user = r->is_user;
+	r->is_user = 0;
 	if ( sig == SIGFPE || sig == SIGSEGV ||
 	     sig == SIGBUS || sig == SIGILL ||
 	     sig == SIGTRAP ) {
-		GET_FAULTINFO_FROM_SC(r->skas.faultinfo, sc);
+		GET_FAULTINFO_FROM_SC(r->faultinfo, sc);
 	}
 
 	change_sig(SIGUSR1, 1);
@@ -62,5 +62,5 @@
 	handler(sig, r);
 
 	errno = save_errno;
-	r->skas.is_user = save_user;
+	r->is_user = save_user;
 }