Bug ID: JDK-8263002 Remove CDS MiscCode region

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JDK 17
17 b13Fixed

The CDS MiscCode region is used for:
(a) C++ vtables
(b) Method trampolines

(a) can be moved to the ReadWrite region
(b) were introduced in JDK-8145221 so we can delay writing into Methods. This was intended to improve copy-on-write sharing to reduce memory footprint. However, this hasn't been shown to have any significant effect (footprint of metadata usually is much smaller than the Java heap), and introduces a lot of complexity in the HotSpot code.

Removing (b) will make it easier to implement JDK-8026297 (Generating AdapterHandlerEntry during CDS dump), which will further improve start-up time.

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Other benefits of removing the MiscCode region:

- We no longer have a read/write/executable region. This address the concern in JDK-8262922.
- We can enable CDS on macOS/AArch64, which does not allow read/write/executable regions. (JDK-8253795)

Duplicate :	JDK-8246015 - Method::link_method is called twice for CDS methods
Relates :	JDK-8263054 - [testbug] SharedArchiveConsistency.java reuses jsa files
Relates :	JDK-8253795 - Implementation of JEP 391: macOS/AArch64 Port
Relates :	JDK-8264240 - [macos_aarch64] enable appcds support after JDK-8263002
Relates :	JDK-8026297 - Generate AdapterHandlerEntry during CDS dump
Relates :	JDK-8262922 - Randomise mapped CDS address and relocate pointers by default
Relates :	JDK-8145221 - Use trampolines for i2i and i2c entries in Methods that are stored in CDS archive