[tlbuild] more library fun

[Norbert Preining]

And one more .. fails in my environmet:
	FAIL: xdvipdfm-bb.test

becasue:
*** xdvipdfmx --ebb picpng.png
libpng warning: Application was compiled with png.h from libpng-1.5.17
libpng warning: Application  is  running with png.c from libpng-1.2.49
libpng error: Incompatible libpng version in application and library

I have the libpng headers installed, but not compiled with --with-system-png

???

Any idea how this happened?

Norbert

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PREINING, Norbert                               http://www.preining.info
JAIST, Japan                                 TeX Live & Debian Developer
DSA: 0x09C5B094   fp: 14DF 2E6C 0307 BE6D AD76  A9C0 D2BF 4AA3 09C5 B094
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