More flexible detection of arm processors to fix cmake errors on armv6l and armv7l devices

Change-Id: Iee7653f620c56136df75908830f06a1d5c597609
Reviewed-on: https://boringssl-review.googlesource.com/12240
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 13fb429..a26af07 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -168,11 +168,7 @@
   set(ARCH "x86")
 elseif (${CMAKE_SYSTEM_PROCESSOR} STREQUAL "i686")
   set(ARCH "x86")
-elseif (${CMAKE_SYSTEM_PROCESSOR} STREQUAL "arm")
-  set(ARCH "arm")
-elseif (${CMAKE_SYSTEM_PROCESSOR} STREQUAL "armv6")
-  set(ARCH "arm")
-elseif (${CMAKE_SYSTEM_PROCESSOR} STREQUAL "armv7-a")
+elseif (${CMAKE_SYSTEM_PROCESSOR} MATCHES "^arm*")
   set(ARCH "arm")
 elseif (${CMAKE_SYSTEM_PROCESSOR} STREQUAL "aarch64")
   set(ARCH "aarch64")