bug, converting hex to int

[larshp]

first bit is the sign,

~fixed~

[larshp]

another testcase,

DATA lv_hex TYPE x LENGTH 4 VALUE 'FF000000'.
DATA lv_int TYPE i.
lv_int = lv_hex.
ASSERT lv_int = -16777216.

DATA lv_hex TYPE x LENGTH 5 VALUE '00FFFFFFFF'.
DATA lv_int TYPE i.
lv_int = lv_hex+1.
ASSERT lv_int = -1.