hdr: fix crash (oss-fuzz)
This patch Fixes crash when RLE data is corrupted (test cases attached).
Should also fixes (no test cases available):
- Issue 62044 in oss-fuzz: kimageformats:kimgio_hdr_fuzzer: Undefined-shift in RGBE_To_QRgbLine
- Issue 62057 in oss-fuzz: kimageformats:kimgio_hdr_fuzzer: Heap-buffer-overflow in Read_Old_Line
Edited by Mirco Miranda