DIPBDIP/DINPBDINP condition checked PORT_W_WIDTH == 71, which never
matches any valid SDP width. Should be 72, matching the DIBDI/DINBDIN
condition on the line above. This caused data bits 68-69 to be
silently overwritten with copies of bits 64-65 on every write.
Affects both xc6v (RAMB36E1, Artix-7/Kintex-7/Virtex-7) and xcu
(RAMB36E2, UltraScale/UltraScale+) mapping templates. The RAMB18E1/E2
equivalents correctly use == 36.
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