idmap2: fix clang-tidy warnings [modernize-*]

Bug: 120024673
Test: mmm frameworks/base/cmds/idmap2; check output
Change-Id: I8768169fb7b541eb6b1aa3311c46a710eb71aac9
diff --git a/cmds/idmap2/libidmap2/RawPrintVisitor.cpp b/cmds/idmap2/libidmap2/RawPrintVisitor.cpp
index a6bf5fb6..ec2decf 100644
--- a/cmds/idmap2/libidmap2/RawPrintVisitor.cpp
+++ b/cmds/idmap2/libidmap2/RawPrintVisitor.cpp
@@ -27,8 +27,7 @@
 
 using android::ApkAssets;
 
-namespace android {
-namespace idmap2 {
+namespace android::idmap2 {
 
 // verbatim copy fomr PrettyPrintVisitor.cpp, move to common utils
 #define RESID(pkg, type, entry) (((pkg) << 24) | ((type) << 16) | (entry))
@@ -127,5 +126,4 @@
   offset_ += kIdmapStringLength;
 }
 
-}  // namespace idmap2
-}  // namespace android
+}  // namespace android::idmap2