Build error: fwts_acpi_tables.c "‘strncat’ specified bound 2 equals source length"

[Rebecca Cran]

I'm getting a build error on Debian aarch64, with gcc 8.3.0 and the 
latest master (b8b673c3f232efcd15ad9693386b3dd195d1dfa1):

fwts_acpi_tables.c: In function ‘fwts_acpi_space_id_check’:
fwts_acpi_tables.c:1683:4: error: ‘strncat’ specified bound 2 equals 
source length [-Werror=stringop-overflow=]
     strncat(must_be_id, ", ", 2);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
fwts_acpi_tables.c:1685:4: error: ‘strncat’ specified bound 4 equals 
source length [-Werror=stringop-overflow=]
     strncat(must_be_id, " or ", 4);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


-- 
Rebecca Cran