libpcap: fix build on microblaze

On microblaze, libpcap needs to be built with -fPIC rather than -fpic as
reported by mrueg on IRC.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/libpcap/libpcap.mk

@@ -21,4 +21,9 @@ LIBPCAP_CONF_ENV = ac_cv_linux_vers=2 \
 		ac_cv_header_linux_wireless_h=yes # configure misdetects this
 LIBPCAP_CONF_OPT = --disable-yydebug --with-pcap=linux
 
+# microblaze needs -fPIC instead of -fpic
+ifeq ($(BR2_microblaze),y)
+LIBPCAP_CONF_ENV += CFLAGS="$(TARGET_CFLAGS) -fPIC"
+endif
+
 $(eval $(autotools-package))