RFR: 8344119: CUPSPrinter does not respect PostScript printer definition specification in case of reading ImageableArea values from PPD files

[GennadiyKrivoshein]

**Description:**
The PR updates sun.print.CUPSPrinter's behavior in terms of reading media imageable area values according to the PostScript Printer Description File Format Specification.
The actual implementation reads X and Y coordinates of the upper right corner of the imageable area as width and height of the imageable area. https://bugs.openjdk.org/browse/JDK-8344119

**Updates:** 
Added subtraction of the X and Y coordinates of the lower left corner to fix the width and height values of the imageable area.

**Tests:**
Tested with `test/jdk/javax/print/DialogMargins.java` using Brother DCP-T720DW, the test draws a black line along the borders of the imageable area.
The test was run with the minimum possible margins.
_Before the fix_: the right and bottom lines are not printed (the right and bottom lines are outside the printable area).
_After the fix_: all lines are printed.

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Commit messages:
 - Merge branch 'openjdk:master' into PPDImageableArea
 - margins calculation does not meet PostScript standard

Changes: https://git.openjdk.org/jdk/pull/22110/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22110&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8344119
  Stats: 5 lines in 1 file changed: 2 ins; 2 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/22110.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22110/head:pull/22110

PR: https://git.openjdk.org/jdk/pull/22110