Add data info for superh (#198)

* Add data info for superh

* fmt

* Fetch symbol data dynamically from resolved.section

* Remove unused var

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Co-authored-by: Luke Street <luke@street.dev>

objdiff-core/src/obj/mod.rs

@@ -109,6 +109,11 @@ impl Section {
         }
     }
 
+    pub fn symbol_data(&self, symbol: &Symbol) -> Option<&[u8]> {
+        let offset = symbol.address.checked_sub(self.address)?;
+        self.data.get(offset as usize..offset as usize + symbol.size as usize)
+    }
+
     // The alignment to use when "Combine data/text sections" is enabled.
     pub fn combined_alignment(&self) -> u64 {
         const MIN_ALIGNMENT: u64 = 4;