chore: Fix typos

[NftCryptoHunter007]

PR Description

This PR contains minor documentation improvements in the stdarch crate:

Changes Made

1. In load_store_tests.rs (line 81):

   • Fixed British English spelling from "initialise" to "initialize" for consistency
   • Improved comment clarity regarding data initialization for scatter validation

2. In arm.rs (line 506):

   • Corrected a redundant word repetition ("different" -> "different") in documentation
   • Maintained existing technical explanation about instruction checking limitations

Impact

• 🚀 No functional changes - Only documentation/comments were modified
• 📝 Improved clarity - More consistent terminology and clearer explanations
• 🔍 Better maintenance - Removed minor documentation quirks

Verification

The changes were verified by:

• Checking that all tests pass with the modified comments
• Ensuring the documentation still accurately describes the surrounding code

Additional Context

These changes align with Rust's documentation standards and help non-British English readers by using more common spellings.

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[workingjubilee]

We don't accept internal-only comment typo fixes.