package/libmbim: fix build with help2man

Fix the following build failure with help2man raised since bump to
version 1.26.0 in commit be76508af2b2253f95137a28198139732be2dcb3:

FAILED: docs/man/mbimcli.1
/usr/bin/help2man --output=docs/man/mbimcli.1 '--name=Control MBIM devices' '--help-option="--help-all"' /home/peko/autobuild/instance-1/output-1/build/libmbim-1.26.0/build/src/mbimcli/mbimcli
help2man: can't get `"--help-all"' info from /home/peko/autobuild/instance-1/output-1/build/libmbim-1.26.0/build/src/mbimcli/mbimcli
Try `--no-discard-stderr' if option outputs to stderr

Fixes:
 - http://autobuild.buildroot.org/results/eaa2ba54b9c74f07292d3cad4fa96c80e6079702

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
(cherry picked from commit a315d7c98bb0a853e9fe84639ea15595d9dd4b85)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libmbim/0002-meson-build-add-an-option-to-not-build-man-pages.patch

@@ -0,0 +1,60 @@
+From 792af73ea90e9689703ab526dd444fdb1c2f8e40 Mon Sep 17 00:00:00 2001
+From: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>
+Date: Thu, 14 Oct 2021 12:25:46 +0200
+Subject: [PATCH] meson.build: add an option to not build man pages.
+
+When cross-compiling, the compiled binaries cannot be run on the build
+machine, unless one defines a helper (e.g. qemu) in the meson
+configuration, which is most of the time undesirable.
+
+If help2man is installed on the build machine, then the build would fail
+because of this, so add an option to disable generating the man pages.
+
+With later versions of meson, it will be possible to automatically
+detect this condition.
+
+[Retrieved (and backported) from:
+https://gitlab.freedesktop.org/mobile-broadband/libmbim/-/commit/792af73ea90e9689703ab526dd444fdb1c2f8e40]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+---
+ meson.build       | 8 +++++++-
+ meson_options.txt | 1 +
+ 2 files changed, 8 insertions(+), 1 deletion(-)
+
+diff --git a/meson.build b/meson.build
+index 1c5ee2d..59f1727 100644
+--- a/meson.build
++++ b/meson.build
+@@ -184,8 +184,8 @@ if enable_gtk_doc
+   subdir('docs/reference/libmbim-glib')
+ endif
+ 
+-help2man = find_program('help2man', required: false)
+-if help2man.found()
++enable_man = get_option('man')
++if enable_man
+   subdir('docs/man')
+ endif
+ 
+@@ -198,6 +203,7 @@ summary({
+ output += '    Documentation:         ' + enable_gtk_doc.to_string() + '\n'
+ output += '    bash completion:       ' + enable_bash_completion.to_string() + '\n'
+ output += '    gobject introspection: ' + enable_gir.to_string() + '\n\n'
++output += '    man pages:             ' + enable_man.to_string() + '\n\n'
+ output += '  System paths\n'
+ output += '    prefix:                ' + mbim_prefix + '\n'
+ output += '    udev base directory:   ' + mbim_username + '\n\n'
+diff --git a/meson_options.txt b/meson_options.txt
+index 1305957..bfa33ab 100644
+--- a/meson_options.txt
++++ b/meson_options.txt
+@@ -7,5 +7,6 @@ option('udevdir', type: 'string', value: '', description: 'where udev base direc
+ 
+ option('introspection', type: 'boolean', value: 'true', description: 'build introspection support')
+ option('gtk_doc', type: 'boolean', value: false, description: 'use gtk-doc to build documentation')
++option('man', type: 'boolean', value: 'true', description: 'build man pages using help2man')
+ 
+ option('bash_completion', type: 'boolean', value: true, description: 'install bash completion files')
+-- 
+GitLab
+

package/libmbim/libmbim.mk

@@ -12,6 +12,7 @@ LIBMBIM_CPE_ID_VENDOR = freedesktop
 LIBMBIM_INSTALL_STAGING = YES
 
 LIBMBIM_DEPENDENCIES = libglib2
+LIBMBIM_CONF_OPTS = -Dman=false
 
 ifeq ($(BR2_PACKAGE_GOBJECT_INTROSPECTION),y)
 LIBMBIM_DEPENDENCIES += gobject-introspection