linux: Add dependency on rsync for Linux >= 5.3

As of Linux v5.3 rsync is used as part of the build process. Add Linux
5.3 as a milestone, configure detection of rsync and a dependency on
rsync for Linux 5.3 and newer. Add a comment in so that users can tell
why they can't select a newer version.

Fixes #1628

Signed-off-by: Chris Packham <judge.packham@gmail.com>

config/configure.in.in

@@ -21,6 +21,9 @@ config CONFIGURE_has_meson
 config CONFIGURE_has_ninja
     @KCONFIG_ninja@
 
+config CONFIGURE_has_rsync
+    @KCONFIG_rsync@
+
 config CONFIGURE_has_make_3_81_or_newer
     @KCONFIG_make_3_81_or_newer@
 

config/kernel/linux.in

@@ -12,6 +12,13 @@
 # (including versions in between) until the EOL dates indicated below.
 # Such pinned versions are indicated in version.desc files with a comment.
 
+config KERNEL_DEP_RSYNC
+    def_bool y
+    select LINUX_REQUIRE_older_than_5_3 if !CONFIGURE_has_rsync
+
+comment "Linux >=5.3 requires rsync"
+    depends on !CONFIGURE_has_rsync
+
 choice
     bool
     prompt "Kernel verbosity:"

configure.ac

@@ -161,6 +161,10 @@ AC_CHECK_PROGS([ninja], [ninja])
 CTNG_SET_KCONFIG_OPTION([ninja])
 AC_SUBST([ninja])
 
+AC_CHECK_PROGS([rsync], [rsync])
+CTNG_SET_KCONFIG_OPTION([rsync])
+AC_SUBST([rsync])
+
 CTNG_CPU_COUNT
 
 CTNG_PATH_TOOL_REQ([PATCH], [gpatch patch], [patch])

packages/linux/package.desc

@@ -2,6 +2,6 @@ origin='www.kernel.org'
 repository='git git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git'
 mirrors='$(CT_Mirrors kernel.org linux ${CT_LINUX_VERSION})'
 relevantpattern='2.*.*|. *.*|.'
-milestones='3.2 3.7 4.8'
+milestones='3.2 3.7 4.8 5.3'
 archive_formats='.tar.xz .tar.gz'
 signature_format='unpacked/.sign'