try_to_set_pmm
have_user_pmlen_7 = try_to_set_pmm(ENVCFG_PMM_PMLEN_7);
have_user_pmlen_16 = try_to_set_pmm(ENVCFG_PMM_PMLEN_16);
fwft->have_vs_pmlen_7 = try_to_set_pmm(ENVCFG_PMM_PMLEN_7);
fwft->have_vs_pmlen_16 = try_to_set_pmm(ENVCFG_PMM_PMLEN_16);