sched: Rename sched.c as sched/core.c in comments and Documentation

Most of the stuff from kernel/sched.c was moved to kernel/sched/core.c long time
back and the comments/Documentation never got updated.

I figured it out when I was going through sched-domains.txt and so thought of
fixing it globally.

I haven't crossed check if the stuff that is referenced in sched/core.c by all
these files is still present and hasn't changed as that wasn't the motive behind
this patch.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/cdff76a265326ab8d71922a1db5be599f20aad45.1370329560.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/Documentation/virtual/uml/UserModeLinux-HOWTO.txt b/Documentation/virtual/uml/UserModeLinux-HOWTO.txt
index a5f8436..f4099ca 100644
--- a/Documentation/virtual/uml/UserModeLinux-HOWTO.txt
+++ b/Documentation/virtual/uml/UserModeLinux-HOWTO.txt
@@ -3127,7 +3127,7 @@
            at process_kern.c:156
        #3  0x1006a052 in switch_to (prev=0x50072000, next=0x507e8000, last=0x50072000)
            at process_kern.c:161
-       #4  0x10001d12 in schedule () at sched.c:777
+       #4  0x10001d12 in schedule () at core.c:777
        #5  0x1006a744 in __down (sem=0x507d241c) at semaphore.c:71
        #6  0x1006aa10 in __down_failed () at semaphore.c:157
        #7  0x1006c5d8 in segv_handler (sc=0x5006e940) at trap_user.c:174
@@ -3191,7 +3191,7 @@
            at process_kern.c:161
        161       _switch_to(prev, next);
        (gdb)
-       #4  0x10001d12 in schedule () at sched.c:777
+       #4  0x10001d12 in schedule () at core.c:777
        777             switch_to(prev, next, prev);
        (gdb)
        #5  0x1006a744 in __down (sem=0x507d241c) at semaphore.c:71