Fix R_AVR_7_PCREL and R_AVR_13_PCREL range checking (#92695)

Fix incorrect range check of R_AVR_7_PCREL. R_AVR_7_PCREL has 7 bits
available, but it works in instruction words and the actual range is [-128, 126].

Disable range check of R_AVR_13_PCREL. This matches the behavior of avr-ld,
and is needed for devices like the ATtiny85 which only have rjmp/rcall but have
8KiB flash memory.