Add ignore SAFESH flags in cmake

[rafagan]

When I run cmake the following error occurs:

PS C:\Users\rafagan\Desktop\sentry-native> cmake --build build --parallel
Microsoft (R) Build Engine version 15.5.180.51428 for .NET Framework
Copyright (C) Microsoft Corporation. All rights reserved.

getopt.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\getopt.lib
zlib.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\zlib.lib
mini_chromium.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\mini_chromium.lib
crashpad_compat.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\crashpad_compat.lib
crashpad_tools.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\crashpad_tools.lib
crashpad_util.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\crashpad_util.lib
crashpad_client.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\crashpad_client.lib
crashpad_snapshot.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\crashpad_snapshot.lib
crashpad_minidump.vcxproj -> C:\Users\rafagan\Desktop\sentry-native\build\crashpad_minidump.lib
crashpad_util.lib(capture_context_win.obj) : error LNK2026: module unsafe for SAFESEH image. [C:\Users\rafagan\Desktop
sentry-native\build\external\crashpad\handler\crashpad_handler.vcxproj]
crashpad_util.lib(safe_terminate_process.obj) : error LNK2026: module unsafe for SAFESEH image. [C:\Users\rafagan\Deskt
op\sentry-native\build\external\crashpad\handler\crashpad_handler.vcxproj]
C:\Users\rafagan\Desktop\sentry-native\build\crashpad_handler.exe : fatal error LNK1281: Unable to generate SAFESEH ima
ge. [C:\Users\rafagan\Desktop\sentry-native\build\external\crashpad\handler\crashpad_handler.vcxproj]

Then I added the following lines and the errors had gone:

SET(CMAKE_CXX_FLAGS           "${CMAKE_CXX_FLAGS} /D \"SAFESEH:NO\"")
SET(CMAKE_EXE_LINKER_FLAGS    "${CMAKE_EXE_LINKER_FLAGS} /SAFESEH:NO")
SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} /SAFESEH:NO")
SET(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} /SAFESEH:NO")

[jan-auer]

@Swatinem It looks like we need to bring back this: #64