openipmi: fix do_configure error when using dash

We encountered a do_configure error when using dash on Ubuntu 20.04:
conftest.c:31:26: fatal error: Python.h: No such file or directory
   31 |                 #include <Python.h>
      |                          ^~~~~~~~~~

It seems that PYTHON_CPPFLAGS is not passed to configure command
correctly. Use configuration option --with-pythoncflags instead of
passing it in cmdline.

Signed-off-by: Yi Zhao <yi.zhao@windriver.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-networking/recipes-support/openipmi/openipmi_2.0.34.bb

@@ -42,7 +42,9 @@ CFLAGS += "-D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64"
 
 EXTRA_OECONF = "--disable-static \
                 --with-perl='${STAGING_BINDIR_NATIVE}/perl-native/perl' \
-                --with-glibver=2.0"
+                --with-glibver=2.0 \
+                --with-pythoncflags='-I${STAGING_INCDIR}/${PYTHON_DIR}${PYTHON_ABI}' \
+               "
 
 PACKAGECONFIG ??= "gdbm"
 PACKAGECONFIG[gdbm] = "ac_cv_header_gdbm_h=yes,ac_cv_header_gdbm_h=no,gdbm,"
@@ -64,7 +66,7 @@ FILES:${PN}-dbg += " \
 
 do_configure () {
     # Let's perform regular configuration first then handle perl issues.
-    PYTHON_CPPFLAGS=-I${STAGING_INCDIR}/${PYTHON_DIR}${PYTHON_ABI} autotools_do_configure
+    autotools_do_configure
 
     perl_ver=`perl -V:version | cut -d\' -f 2`