Change crtbrand for host bionic

Fixes a build error when PLATFORM_SDK_VERSION is not set.

Bug: 31559095
Test: attempt to build host bionic
Change-Id: I9cbdcea206ef1239c330a5adafbfa5cc797fef5e
diff --git a/libc/arch-common/bionic/crtbrand.S b/libc/arch-common/bionic/crtbrand.S
index 4b4f99c..34d6480 100644
--- a/libc/arch-common/bionic/crtbrand.S
+++ b/libc/arch-common/bionic/crtbrand.S
@@ -33,7 +33,12 @@
   .long 2f-1f                 // int32_t namesz
   .long 3f-2f                 // int32_t descsz
   .long 1                     // int32_t type
+#ifdef __ANDROID__
 1:.ascii "Android\0"          // char name[]
 2:.long PLATFORM_SDK_VERSION  // int32_t android_api
+#else
+1:.ascii "LinuxBionic\0"      // char name[]
+2:
+#endif
 3:
   .size abitag, .-abitag