mount-matrix: Fix stringop-overflow warnings
iio-sensor-proxy/src/accel-mount-matrix.c:77:21: warning: ‘parse_mount_matrix’ accessing 24 bytes in a region of size 8 [-Wstringop-overflow=]
77 | if (parse_mount_matrix (mount_matrix, &ret))
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
iio-sensor-proxy/src/accel-mount-matrix.c:77:21: note: referencing argument 2 of type ‘AccelVec3 **’
iio-sensor-proxy/src/accel-mount-matrix.c:91:1: note: in a call to function ‘parse_mount_matrix’
91 | parse_mount_matrix (const char *mtx,
| ^~~~~~~~~~~~~~~~~~
Edited by Bastien Nocera