qtbase: use v5.12.0 as base

* restore 0018-Fix-compile-issue-with-gcc-9.patch which is only in v5.12.1
* zlib detection got broken probably in:
  commit e80bf655e922e9864f8843b5e7bbb47019a6d95a
  Author: Oswald Buddenhagen <oswald.buddenhagen@qt.io>
  Date:   Thu Dec 7 19:30:07 2017 +0100

    configure: verify header presence against sources

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/recipes-qt/qt5/qtbase/0004-configure-bump-path-length-from-256-to-512-character.patch b/recipes-qt/qt5/qtbase/0004-configure-bump-path-length-from-256-to-512-character.patch
index 4b48081e..eb866c7e 100644
--- a/recipes-qt/qt5/qtbase/0004-configure-bump-path-length-from-256-to-512-character.patch
+++ b/recipes-qt/qt5/qtbase/0004-configure-bump-path-length-from-256-to-512-character.patch
@@ -1,4 +1,4 @@
-From 3f34b8d782f26876e4e62c6201454ea74ef90ab3 Mon Sep 17 00:00:00 2001
+From 394f8c1f2faae7cf54dc6882b3817c226d84152c Mon Sep 17 00:00:00 2001
 From: Denys Dmytriyenko <denys@ti.com>
 Date: Tue, 25 Aug 2015 10:05:15 -0400
 Subject: [PATCH] configure: bump path length from 256 to 512 characters
@@ -15,10 +15,10 @@ Signed-off-by: Denys Dmytriyenko <denys@ti.com>
  1 file changed, 3 insertions(+), 3 deletions(-)
 
 diff --git a/configure.pri b/configure.pri
-index b3b3e27c44..45b5495bfd 100644
+index 64ed6b9ed8..bb2acbcd35 100644
 --- a/configure.pri
 +++ b/configure.pri
-@@ -837,10 +837,10 @@ defineTest(qtConfOutput_preparePaths) {
+@@ -838,10 +838,10 @@ defineTest(qtConfOutput_preparePaths) {
          "static const char qt_configure_installation     [12+11]  = \"qt_instdate=2012-12-20\";" \
          "" \
          "/* Installation Info */" \