arc: ptrace: hard-code "arc" instead of UTS_MACHINE

ARC uses the UTS_MACHINE defined in the top Makefile as follows:

  UTS_MACHINE     := $(ARCH)

We know it is "arc" when we are building the kernel for ARC.
Hard-code user_regset_view::name, like many other architectures do.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/kernel/Makefile

@@ -3,9 +3,6 @@
 # Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 #
 
-# Pass UTS_MACHINE for user_regset definition
-CFLAGS_ptrace.o		+= -DUTS_MACHINE='"$(UTS_MACHINE)"'
-
 obj-y	:= arcksyms.o setup.o irq.o reset.o ptrace.o process.o devtree.o
 obj-y	+= signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o
 obj-$(CONFIG_ISA_ARCOMPACT)		+= entry-compact.o intc-compact.o

arch/arc/kernel/ptrace.c

@@ -253,7 +253,7 @@ static const struct user_regset arc_regsets[] = {
 };
 
 static const struct user_regset_view user_arc_view = {
-	.name		= UTS_MACHINE,
+	.name		= "arc",
 	.e_machine	= EM_ARC_INUSE,
 	.regsets	= arc_regsets,
 	.n		= ARRAY_SIZE(arc_regsets)