Failed to build for EL 7

Hi

Could you please fix build against RHEL 7:

gcc -c -o adaptivemmd.o adaptivemmd.c -I. -Wall -g
adaptivemmd.c: In function 'get_unmapped_pages':
adaptivemmd.c:977:21: error: 'KPF_PGTABLE' undeclared (first use in this function)
    if ((pageflg[i]>>KPF_PGTABLE) & 1)
                     ^
adaptivemmd.c:977:21: note: each undeclared identifier is reported only once for each function it appears in
make: *** [adaptivemmd.o] Error 1

What version of kernel-headers do you have? You can check with rpm -qa | grep headers. KPF_PGTABLE is only available since v4.18