fix autogen macro for detection pg client lib

Author: okbob

README.md

@@ -707,8 +707,6 @@ If you want to use `pspg` as Postgres client, then you need run
 I had to install `openssl-devel` package and I had to set
 `export PKG_CONFIG_PATH="/usr/local/pgsql/master/lib/pkgconfig/"`.
 
-Note: the compilation based on usage of `pg_config` is broken.
-
 On FreeBsd you should to use `gmake` instead `make`.
 
 ## Note - Installation details

configure

@@ -6672,7 +6672,7 @@ else
 fi ;;
 esac
 fi
-    if test "X$found_postgresql" = "no"
+    if test "X$found_postgresql" = "Xno"
 then :
   break
 fi

tools/m4_ax_lib_postgresql.m4

@@ -117,7 +117,7 @@ AC_DEFUN([_AX_LIB_POSTGRESQL_PKG_CONFIG],
 	  [PKG_CHECK_EXISTS([libpq],[found_postgresql_pkg_config=yes],[found_postgresql=no])],
 	  [PKG_CHECK_EXISTS([libpq >= "$postgresql_version_req"],
 			   [found_postgresql=yes],[found_postgresql=no])])
-    AS_IF([test "X$found_postgresql" = "no"],[break])
+    AS_IF([test "X$found_postgresql" = "Xno"],[break])
 
     AC_CACHE_CHECK([for the PostgreSQL libraries CPPFLAGS],[ac_cv_POSTGRESQL_CPPFLAGS],
 		   [ac_cv_POSTGRESQL_CPPFLAGS="`$PKG_CONFIG libpq --cflags-only-I`" || _AX_LIB_POSTGRESQL_PKG_CONFIG_fail=yes])