[android] fix 32 bit android build

[hyp]

This fixes the following errors:

S:/SourceCache/swift-testing/Sources/Testing/Support/FileHandle.swift:423:70: error: cannot convert value of type 'UInt32' to expected argument type 'mode_t' (aka 'UInt16')
421 |       }
422 |       var statStruct = stat()
423 |       return (0 == fstat(fd, &statStruct) && swt_S_ISFIFO(statStruct.st_mode))
    |                                                                      `- error: cannot convert value of type 'UInt32' to expected argument type 'mode_t' (aka 'UInt16')
424 |     }
425 | #elseif os(Windows)
S:/SourceCache/swift-testing/Sources/Testing/Support/GetSymbol.swift:34:73: error: integer literal '4294967295' overflows when stored into 'Int'
32 | private nonisolated(unsafe) let RTLD_DEFAULT = ImageAddress(bitPattern: -2)
33 | #elseif os(Android) && _pointerBitWidth(_32)
34 | private nonisolated(unsafe) let RTLD_DEFAULT = ImageAddress(bitPattern: 0xFFFFFFFF)
   |                                                                         `- error: integer literal '4294967295' overflows when stored into 'Int'

Motivation:

Fix 32 bit android build.

Modifications:

Add explicit types to to cast correctly and to pick correct overload.

Result:

Android swift-testing will build for armv7k and i686.

Checklist:

• Code and documentation should follow the style of the Style Guide.
• If public symbols are renamed or modified, DocC references should be updated.

[hyp]

@swift-ci please test

[grynspan]

@compnerd Mind reviewing? Looks correct to me.

[grynspan]

@hyp Note if you need this fix in Swift 6.0.1, please clone the PR and nominate it using the procedure outlined here.