Fix libopenjpeg 1.5 detection on some systems

Someone somewhere decided the pc file will be called libopenjpeg1 instead of libopenjpeg

Bug #78389
diff --git a/configure.ac b/configure.ac
index 0e703d5..fdfe570 100644
--- a/configure.ac
+++ b/configure.ac
@@ -173,7 +173,10 @@
   AC_DEFINE(ENABLE_LIBOPENJPEG)
   PKG_CHECK_EXISTS(libopenjpeg >= 1.5,
       [AC_DEFINE(WITH_OPENJPEG_IGNORE_PCLR_CMAP_CDEF_FLAG, 1, [OpenJPEG with the OPJ_DPARAMETERS_IGNORE_PCLR_CMAP_CDEF_FLAG flag.])],
-      [])
+      [PKG_CHECK_EXISTS(libopenjpeg1 >= 1.5,
+       [AC_DEFINE(WITH_OPENJPEG_IGNORE_PCLR_CMAP_CDEF_FLAG, 1, [OpenJPEG with the OPJ_DPARAMETERS_IGNORE_PCLR_CMAP_CDEF_FLAG flag.])],
+       [])
+      ])
 fi
 
 AM_CONDITIONAL(BUILD_LIBOPENJPEG, test x$enable_libopenjpeg = xyes)