Bug#997045: saga: missing build dependency on pkg-config

[Adrian Bunk]

Source: saga
Version: 7.3.0+dfsg-5
Severity: serious
Tags: ftbfs

https://tests.reproducible-builds.org/debian/rb-pkg/bookworm/amd64/saga.html
https://buildd.debian.org/status/logs.php?pkg=saga&ver=7.3.0%2Bdfsg-5%2Bb2

...
checking for omp_get_num_threads in -lgomp... yes
checking for libsvm/svm.h... yes
checking for svm_get_svm_type in -lsvm... yes
./configure: line 17489: syntax error near unexpected token `DXFLIB,'
./configure: line 17489: `PKG_CHECK_MODULES(DXFLIB, dxflib, LIBDXFFOUND=1,LIBDXFFOUND=0)'