RFR: 8287400: Make BitMap range parameter names consistent

[David Holmes]

On Sat, 26 Nov 2022 22:16:34 GMT, Afshin Zafari <duke at openjdk.org> wrote:

> The ranges are determined by 'start' and 'end' all over the bitMap.hpp and bitMap.cpp. All instances of other names for start and end are replaced.

I only see one use of `start_offset`  in bitMap.cpp and no uses of `start` in bitMap.hpp - so this is really changing the vast majority of the names. The simplest change for consistency would be to always use `beg` and `end`.

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PR: https://git.openjdk.org/jdk/pull/11375