misc: Remove the Linux namespace

This namespace has gone through the deprecation period
and can now be removed.

Change-Id: I73d7792ab8897d00b143d82d0fb70987ca410438
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/67364
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Richard Cooper <richard.cooper@arm.com>

src/arch/generic/linux/threadinfo.hh

@@ -36,7 +36,6 @@
 namespace gem5
 {
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {
 

src/arch/mips/linux/hwrpb.hh

@@ -30,7 +30,6 @@
 namespace gem5
 {
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {
     struct pcb_struct

src/arch/mips/linux/thread_info.hh

@@ -34,7 +34,6 @@
 namespace gem5
 {
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {
     struct thread_info

src/kern/linux/events.cc

@@ -54,7 +54,6 @@
 namespace gem5
 {
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {
 

src/kern/linux/events.hh

@@ -57,7 +57,6 @@ namespace gem5
 
 class ThreadContext;
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {
 

src/kern/linux/helpers.hh

@@ -47,7 +47,6 @@ namespace gem5
 
 class ThreadContext;
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {
 

src/kern/linux/printk.cc

@@ -42,7 +42,6 @@
 namespace gem5
 {
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {
 

src/kern/linux/printk.hh

@@ -38,7 +38,6 @@
 namespace gem5
 {
 
-GEM5_DEPRECATED_NAMESPACE(Linux, linux);
 namespace linux
 {