libical: tidy up Perl finding

Instead of patching out the Perl detection, seed the search for perl with
HOSTTOOLS_DIR/perl.  This search usually fails because we don't let
find_program() hunt in the system paths currently.

(From OE-Core rev: 802091c09091b71814cbdce0ec3323741862f807)

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-support/libical/libical/Remove-cmake-check-for-Perl.patch

@@ -1,30 +0,0 @@
-From 918cd8764a845a9d25918a444fbaa5070d2be609 Mon Sep 17 00:00:00 2001
-From: Jussi Kukkonen <jussi.kukkonen@intel.com>
-Date: Fri, 21 Aug 2015 16:38:05 +0300
-Subject: [PATCH] Remove cmake check for Perl
-
-We set "CMAKE_FIND_ROOT_PATH_MODE_PROGRAM ONLY" in cmake bbclass to
-make sure cmake does not find host programs. In this case we actually
-are fine with host perl: remove the check.
-
-Upstream-Status: Inappropriate [workaround]
-
-Signed-off-by: Jussi Kukkonen <jussi.kukkonen@intel.com>
----
- CMakeLists.txt | 3 +--
- 1 file changed, 1 insertion(+), 2 deletions(-)
-
-Index: libical-2.0.0/CMakeLists.txt
-===================================================================
---- libical-2.0.0.orig/CMakeLists.txt
-+++ libical-2.0.0/CMakeLists.txt
-@@ -116,8 +116,7 @@ if(SHARED_ONLY)
-   set(LIBRARY_TYPE SHARED)
- endif()
- 
--# must have Perl to create the derived stuff
--find_package(Perl REQUIRED)
-+set(PERL_EXECUTABLE perl)
- 
- # Ensure finding 64bit libs when using 64-bit compilers
- if(CMAKE_CL_64)

meta/recipes-support/libical/libical_2.0.0.bb

@@ -7,7 +7,6 @@ LIC_FILES_CHKSUM = "file://COPYING;md5=d4fc58309d8ed46587ac63bb449d82f8 \
 SECTION = "libs"
 
 SRC_URI = "https://github.com/${BPN}/${BPN}/releases/download/v${PV}/${BP}.tar.gz \
-           file://Remove-cmake-check-for-Perl.patch \
            file://0001-CMakeLists.txt-libical.pc.in-fix-iculibs-remove-full.patch \
            "
 DEPENDS = "icu"
@@ -18,6 +17,9 @@ UPSTREAM_CHECK_URI = "https://github.com/libical/libical/releases"
 
 inherit cmake pkgconfig
 
+# No need to use perl-native, the host perl is sufficient.
+EXTRA_OECMAKE += "-DPERL_EXECUTABLE=${HOSTTOOLS_DIR}/perl"
+
 do_install_append_class-target () {
     # Remove build host references
     sed -i \