[foreign-memaccess+abi] RFR: Fix javadoc issues in MemorySegment::copy [v2]

[Maurizio Cimadamore]

> This PR fixes few issues in the specification of `MemorySegment::copy`:
> 
> * in some code snippets `srcSegment` and `dstSegment` is followed by parenthesis (e.g. like a method call)
> * the more general segment-to-segment `MemorySegment::copy` overload is missing a `throws` clause for when src segment is out of bounds
> * the less general segment-to-segment `MemorySegment::copy` could use some splitting of its `throws` clauses, to make it more consistent with other methods

Maurizio Cimadamore has updated the pull request incrementally with one additional commit since the last revision:

  Split javadoc throws

-------------

Changes:
  - all: https://git.openjdk.org/panama-foreign/pull/879/files
  - new: https://git.openjdk.org/panama-foreign/pull/879/files/528252b6..b2719b6e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=panama-foreign&pr=879&range=01
 - incr: https://webrevs.openjdk.org/?repo=panama-foreign&pr=879&range=00-01

  Stats: 3 lines in 1 file changed: 1 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/panama-foreign/pull/879.diff
  Fetch: git fetch https://git.openjdk.org/panama-foreign.git pull/879/head:pull/879

PR: https://git.openjdk.org/panama-foreign/pull/879