configure: output more compile settings

Add information on CPPFLAGS, LDFLAGS and LIBS to the end of the
configure output. This is very helpful in tracing issues when
adjusting the configure file and also will allow us to more
easily replicate any issues discovered due to a users build
environment.

Signed-off-by: Allan McRae <allan@archlinux.org>
Signed-off-by: Dan McGee <dan@archlinux.org>

configure.ac

@@ -398,9 +398,13 @@ ${PACKAGE_NAME}:
     localstatedir          : $(eval echo ${localstatedir})
        database dir        : $(eval echo ${localstatedir})/lib/pacman/
        cache dir           : $(eval echo ${localstatedir})/cache/pacman/pkg/
+
     compiler               : ${CC}
+    preprocessor flags     : ${CPPFLAGS}
     compiler flags         : ${CFLAGS}
     defines                : ${DEFS}
+    library flags          : ${LIBS}
+    linker flags           : ${LDFLAGS}
 
     Architecture           : ${CARCH}
     Architecture flags     : ${CARCHFLAGS}