linux-user: remove configure option for setting uname release

--enable-uname-release was a rather heavyweight hammer, as it allows
providing values less that UNAME_MINIMUM_RELEASE. Also, it affects
all built linux-user targets, which in most cases is not what user
wants.

Now that we have UNAME_MINIMUM_RELEASE for all linux-user platforms,
we can drop --enable-uname-release and the related CONFIG_UNAME_RELEASE
define.

Users can still override the variable with QEMU_UNAME=2.6.32 or -r
command line option. If distributors need to update a minimum version
for a specific target, it can be done by updating UNAME_MINIMUM_RELEASE.

Signed-off-by: Riku Voipio <riku.voipio@linaro.org>

configure

@@ -285,7 +285,6 @@ softmmu="yes"
 linux_user="no"
 bsd_user="no"
 guest_base="yes"
-uname_release=""
 aix="no"
 blobs="yes"
 pkgversion=""
@@ -945,8 +944,6 @@ for opt do
   ;;
   --disable-pie) pie="no"
   ;;
-  --enable-uname-release=*) uname_release="$optarg"
-  ;;
   --enable-werror) werror="yes"
   ;;
   --disable-werror) werror="no"
@@ -1295,7 +1292,6 @@ Advanced options (experts only):
   --fmod-lib               path to FMOD library
   --fmod-inc               path to FMOD includes
   --oss-lib                path to OSS library
-  --enable-uname-release=R Return R for uname -r in usermode emulation
   --cpu=CPU                Build for host CPU [$cpu]
   --disable-uuid           disable uuid support
   --enable-uuid            enable uuid support
@@ -4128,8 +4124,6 @@ echo "xen support       $xen"
 echo "brlapi support    $brlapi"
 echo "bluez  support    $bluez"
 echo "Documentation     $docs"
-[ ! -z "$uname_release" ] && \
-echo "uname -r          $uname_release"
 echo "GUEST_BASE        $guest_base"
 echo "PIE               $pie"
 echo "vde support       $vde"
@@ -4544,8 +4538,6 @@ if [ "$bsd" = "yes" ] ; then
   echo "CONFIG_BSD=y" >> $config_host_mak
 fi
 
-echo "CONFIG_UNAME_RELEASE=\"$uname_release\"" >> $config_host_mak
-
 if test "$zero_malloc" = "yes" ; then
   echo "CONFIG_ZERO_MALLOC=y" >> $config_host_mak
 fi

linux-user/main.c

@@ -69,7 +69,7 @@ unsigned long reserved_va;
 static void usage(void);
 
 static const char *interp_prefix = CONFIG_QEMU_INTERP_PREFIX;
-const char *qemu_uname_release = CONFIG_UNAME_RELEASE;
+const char *qemu_uname_release;
 
 /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
    we allocate a bigger stack. Need a better solution, for example

linux-user/uname.c

@@ -155,7 +155,6 @@ void init_qemu_uname_release(void)
      * a specific fake version number, we might want to fake a minimum
      * target kernel version.
      */
-#ifdef UNAME_MINIMUM_RELEASE
     struct new_utsname buf;
 
     if (qemu_uname_release && *qemu_uname_release) {
@@ -169,5 +168,4 @@ void init_qemu_uname_release(void)
     if (relstr_to_int(buf.release) < relstr_to_int(UNAME_MINIMUM_RELEASE)) {
         qemu_uname_release = UNAME_MINIMUM_RELEASE;
     }
-#endif
 }