NaN check for trapezoidal routines.

[ACSimon33]

Description

Following up on #737 I've implemented a NaN check for trapezoidal matrices. I've added adirect argument to support a whole bunch of trapezoidal matrices (e.g. those which occur in xLARFB):

Diagonals 'F' (front / forward) and 'B' (back / backward):

        A = ( F       )           A = ( F     B       )
            (    F    )               (    F     B    )
            ( B     F )               (       F     B )
            (    B    )
            (       B )

      direct = 'F', uplo = 'L':

        A = ( *       )           A = ( *             )
            ( *  *    )               ( *  *          )
            ( *  *  * )               ( *  *  *       )
            ( *  *  * )
            ( *  *  * )

      direct = 'F', uplo = 'U':

        A = ( *  *  * )           A = ( *  *  *  *  * )
            (    *  * )               (    *  *  *  * )
            (       * )               (       *  *  * )
            (         )
            (         )

      direct = 'B', uplo = 'L':

        A = (         )           A = ( *  *  *       )
            (         )               ( *  *  *  *    )
            ( *       )               ( *  *  *  *  * )
            ( *  *    )
            ( *  *  * )

      direct = 'B', uplo = 'U':

        A = ( *  *  * )           A = (       *  *  * )
            ( *  *  * )               (          *  * )
            ( *  *  * )               (             * )
            (    *  * )
            (       * )

For now, I've only applied the new NaN check to LAPACKE_?lantr. But the NaN check is designed to also work for LAPACKE_?larfb and potential other routines. @langou I'll investigate those later since I want first confirm with you that the interface that I've chosen is alright.

Additionally, I fixed some missing symbols in the Makefile which I forgot to add in my last PR for #722.

Checklist

• Fixed missing symbols for LAPACKE_?langb in Makefile.
• Implemented NaN check for trapezoidal matrices.
• Fixed NaN check in LAPACKE_?lantr.
• Apply trapezoidal NaN check in LAPACKE_?larfb and maybe other routines.
• Closes NaN check in LAPACKE_?lantr isn't correct for m != n #737

[langou]

Thanks @ACSimon33. This is great. I like the pictures of the matrices occurring in LARFB, very nicely done.