message: build: Drop unused use_pkgconfig variable
diff: @@ -568,7 +568,6 @@ AC_ARG_WITH([daemon],
  [build_bitcoind=$withval],
  [build_bitcoind=yes])
  -use_pkgconfig=yes
  case $host in
  *mingw*)
  TARGET_OS=windows
  @@ -674,14 +673,10 @@ case $host in
  ;;
  esac
  -if test x$use_pkgconfig = xyes; then
  - m4_ifndef([PKG_PROG_PKG_CONFIG], [AC_MSG_ERROR(PKG_PROG_PKG_CONFIG macro not found. Please install pkg-config and re-run autogen.sh.)])
  - m4_ifdef([PKG_PROG_PKG_CONFIG], [
  +m4_ifndef([PKG_PROG_PKG_CONFIG], [AC_MSG_ERROR([PKG_PROG_PKG_CONFIG macro not found. Please install pkg-config and re-run autogen.sh])])
  PKG_PROG_PKG_CONFIG
  - if test x"$PKG_CONFIG" = "x"; then
  - AC_MSG_ERROR(pkg-config not found.)
  - fi
  - ])
  +if test "x$PKG_CONFIG" = x; then
  + AC_MSG_ERROR([pkg-config not found])
  fi
  if test x$use_extended_functional_tests != xno; then
  