[NFC][ELF][Hexagon] Avoid pointless ArrayRef::drop_front

Fixes: b42f96b ("[lld] Add thunks for hexagon (llvm#111217)")
(cherry picked from commit de15d36)

Author: jrtc27

lld/ELF/Relocations.cpp

@@ -2154,9 +2154,8 @@ static int getHexagonPacketOffset(const InputSection &isec,
     if (i == 3 || rel.offset < (i + 1) * 4)
       return i * 4;
     uint32_t instWord = 0;
-    const ArrayRef<uint8_t> instWordContents =
-        data.drop_front(rel.offset - (i + 1) * 4);
-    memcpy(&instWord, instWordContents.data(), sizeof(instWord));
+    memcpy(&instWord, data.data() + (rel.offset - (i + 1) * 4),
+           sizeof(instWord));
     if (((instWord & HEXAGON_MASK_END_PACKET) == HEXAGON_END_OF_PACKET) ||
         ((instWord & HEXAGON_MASK_END_PACKET) == HEXAGON_END_OF_DUPLEX))
       return i * 4;